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Guide 07 of 31

SAT words about certainty and doubt.

80 words the Digital SAT draws on when a passage turns to certainty and doubt — each with its part of speech, a plain-English definition, and an example sentence showing how it behaves in context.

80 words · Free PDF · No account needed

Vocabulary on the Digital SAT is tested in context, not in isolation: a Words in Context question hands you a sentence with a blank and four plausible-looking candidates, and the winner is the one whose shade of meaning fits. Studying words in a meaning-group like this one is the fastest way to build that discrimination — you learn certainty and doubt as a spectrum rather than as 80 unrelated definitions.

Read the definition, then the example sentence. Say the word aloud. Come back to this theme a few days later and cover the definitions — recalling a word cold is what fixes it, and rereading it is not.

The 80 words

Alphabetical. Everything in the Certainty & Doubt guide.

001
adamantadjective

refusing to be persuaded

He was adamant that he was right.

002
ambivalencenoun

the state of having mixed or contradictory feelings

She felt ambivalence about moving to a new city for the job.

003
ambivalentadjective

having mixed feelings about something

She felt ambivalent about accepting the job.

004
anticipateverb

to expect or predict something will happen

We anticipate a large turnout for the annual festival.

005
anticipatingverb

expecting or looking forward to something

She was anticipating the arrival of her guests with excitement.

006
approximateadjective

close to an exact amount but not precise

The approximate cost of the project is two million dollars.

007
categoricaladjective

unqualified; absolute

He issued a categorical denial.

008
certainadjective

known for sure; established beyond doubt

It is certain that changes will occur.

009
chooseverb

to select from available options

You may choose any dessert from the menu.

010
concludeverb

to bring to an end; to reach a decision through reasoning

Based on the data, we can conclude that the treatment is effective.

011
confidentadjective

having strong belief in oneself or something

She felt confident about her chances of winning the competition.

012
confidentadjective

feeling certain about something

She was confident of success.

013
confirmverb

to establish the truth or correctness of something

Please confirm your attendance by Friday.

014
convincedadjective

completely certain about something

She was convinced of his innocence.

015
decidingverb

making a choice or reaching a conclusion about something

After much deliberation, she was finally deciding which university to attend.

016
decisionnoun

a conclusion or resolution reached after consideration

The committee announced their decision to approve the new policy.

017
decisiveadjective

settling an issue or producing a definite result; having the ability to make decisions quickly

Her decisive leadership helped the team navigate through the crisis.

018
decisiveadjective

settling an issue; producing a definite result

The decisive victory ended the debate.

019
definiteadjective

clearly stated or decided; not vague or doubtful

We need a definite answer by Friday to proceed with the project.

020
definiteadjective

clearly stated or decided

We need a definite answer by tomorrow.

021
deliberationnoun

long and careful consideration or discussion

After hours of deliberation, the jury reached a unanimous verdict.

022
determinedadjective/verb

having made a firm decision; resolved; having discovered through investigation

The determined athlete trained for months to compete in the marathon.

023
doubtedverb

felt uncertain about; questioned the truth of

Many people doubted his ability to complete such a challenging task.

024
doubtfuladjective

feeling uncertain about something

The outcome remained doubtful.

025
doubtsnoun/verb

feelings of uncertainty; questions or reservations

She had serious doubts about the accuracy of the financial report.

026
dubiousadjective

hesitating or doubting; questionable

The dubious claim required verification.

027
ensuredverb

made certain that something would happen or be the case

The safety measures ensured that no accidents occurred during construction.

028
ensuringverb

making certain that something happens or is the case

Quality control is essential for ensuring customer satisfaction.

029
equivocaladjective

open to more than one interpretation

His equivocal response raised suspicions.

030
guessverb

to estimate or suppose something without sufficient information to be certain

I can only guess what he meant by that cryptic message.

031
hesitantadjective

tentative, unsure, or slow in acting

She was hesitant to speak up in meetings.

032
hypothesisnoun

a proposed explanation made on the basis of limited evidence as a starting point for investigation

The researcher developed a hypothesis to explain the unusual phenomenon.

033
hypothesizedverb

put forward as a hypothesis; proposed as an explanation

Darwin hypothesized that species evolve through natural selection.

034
implicationnoun

a conclusion that can be drawn from something not explicitly stated; a likely consequence

The implication of his words was that he planned to resign.

035
implicitadjective

implied though not directly expressed; absolute and unquestioning

There was an implicit understanding between them that needed no words.

036
inconclusiveadjective

not leading to a definite conclusion or result

The test results were inconclusive, requiring further investigation.

037
indecisiveadjective

unable to make decisions quickly

His indecisive nature frustrated colleagues.

038
indicationsnoun

signs or pieces of evidence that suggest something

There were clear indications that the economy was recovering.

039
indicatornoun

a thing that indicates the state or level of something

Rising unemployment is often an indicator of economic trouble.

040
indisputableadjective

unable to be challenged or denied; unquestionable

The evidence against the defendant was indisputable.

041
inevitableadjective

certain to happen; unavoidable

Change is inevitable in a rapidly evolving industry.

042
notionaladjective

existing only in theory or as an idea; not based on reality

The budget figures are notional and may change significantly.

043
opinionnoun

a personal view or judgment not necessarily based on fact

In my opinion, the book was better than the movie adaptation.

044
positiveadjective

with no possibility of doubt; certain

She was positive she had seen him before.

045
precariousnessnoun

the state of being uncertain, unstable, or insecure

The precariousness of her financial situation caused great stress.

046
predeterminedadjective

established or decided in advance

The outcome seemed predetermined before the trial even began.

047
predictableadjective

able to be expected or foreseen; behaving as expected

The movie's ending was predictable from the very first scene.

048
predictedverb

stated that something would happen in the future

Scientists predicted the storm would make landfall by evening.

049
predictingverb

stating what will happen in the future based on evidence

Economists are predicting a recession within the next year.

050
predictionnoun

a statement about what will happen in the future

Her prediction about the election results proved to be accurate.

051
predictiveadjective

relating to or capable of predicting future events

The software uses predictive analytics to forecast sales trends.

052
premeditatedadjective

planned or thought out beforehand

The jury found that the crime was premeditated murder.

053
probabilitynoun

the likelihood that something will happen

There is a high probability of rain tomorrow according to forecasts.

054
questionnoun/verb

a sentence or phrase used to find out information; to ask or express doubt about something

She raised an important question during the meeting.

055
questionableadjective

doubtful or uncertain; open to question or dispute

His questionable business practices raised concerns among investors.

056
questionedverb

asked questions of someone; expressed doubt about something

The detective questioned the witness for several hours.

057
realisticadjective

having a sensible and practical idea of what can be achieved; representing things as they actually are

We need to set realistic goals for the project.

058
resoluteadjective

admirably purposeful and determined

She remained resolute in her decision.

059
selectverb/adjective

to carefully choose as being the best or most suitable

Please select the items you wish to purchase.

060
selectingverb

carefully choosing from a number of alternatives

The committee is selecting candidates for the scholarship.

061
selectsverb

carefully chooses as being the best or most suitable

The chef selects only the freshest ingredients for the dish.

062
skepticaladjective

not easily convinced; having doubts or reservations

Scientists remain skeptical of the unproven treatment.

063
skepticaladjective

not easily convinced; having doubts

Scientists remained skeptical of the claims.

064
speculateverb

to form a theory without firm evidence; to invest in risky ventures

It would be unwise to speculate about the outcome of the election.

065
speculatedverb

formed a theory without firm evidence; engaged in risky financial transactions

Analysts speculated that the company would merge with its competitor.

066
speculatesverb

forms theories without firm evidence; engages in risky financial transactions

The article speculates about future technological developments.

067
suppositionnoun

an uncertain belief; an assumption or hypothesis

His theory is based on supposition rather than evidence.

068
surmisedverb

supposed that something is true without having evidence to confirm it

She surmised from his expression that the news was bad.

069
suspectverb/noun/adjective

to believe something is likely or true without proof; a person thought to be guilty

Police suspect the fire was started deliberately.

070
tentativeadjective

not certain or fixed; provisional

They made tentative plans for the weekend.

071
tenuousadjective

very weak, slight, or insubstantial; lacking a sound basis

The connection between the two events was tenuous at best.

072
uncertainadjective

not able to be relied on; not known or definite

The outcome of the election remained uncertain until the final votes were counted.

073
uncertaintynoun

the state of being unsure or doubtful; something that is not known

There was great uncertainty about what the future would bring.

074
undeniableadjective

unable to be denied or disputed; unquestionable

Her talent as a pianist was undeniable from a very young age.

075
unequivocaladjective

leaving no doubt; unambiguous

The evidence was unequivocal.

076
unpredictableadjective

not able to be predicted; changeable or erratic

The weather in the mountains can be quite unpredictable during spring.

077
unwaveringadjective

steady or resolute; not wavering

Her unwavering support sustained him.

078
vacillateverb

to waver between different opinions or actions

She vacillated between accepting and rejecting the offer.

079
vacillatingadjective

wavering between different opinions

His vacillating stance confused supporters.

080
waveringadjective

becoming unsteady or uncertain

His wavering commitment concerned the team.

Prefer paper? The printable Certainty & Doubt guide adds a memory cue to every entry, ready to print — 76 of the 80 words on this page. For the alphabetical master list, see the SAT vocabulary list; to be quizzed on these words instead of reading them, use the vocabulary trainer or try some Words in Context practice.

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