← TOEFL Prep

TOEFL Vocabulary: Research and data

40 medium-tier words, each with a short plain-English definition, followed by a quick quiz to check what stuck.

Test Ninjas Research · Updated October 1, 2026

Samples, variables, procedures and trends: the words a lecturer uses to describe a study and what it found. Knowing them lets you follow the logic of an experiment in a talk or passage without getting stuck on the method.

Most useful for: Complete the Words · Read an Academic Passage · Listen to an Academic Talk.

Research and data is one of the medium themes in our TOEFL vocabulary list, where you can also find how the tiers work.

The 40 words

Research and data — Medium tier
#WordMeaningTier
1abstracta short summary of a research workMedium
2accuracyhow closely a measurement matches realityMedium
3assessto judge after examining evidenceMedium
4baselinea starting measure used for comparisonMedium
5categorya group whose members share a featureMedium
6codeto assign labels to information for analysisMedium
7compileto bring information together in one placeMedium
8correlateto vary together in a measurable wayMedium
9criteriastandards used to make a judgmentMedium
10databasean organized collection of informationMedium
11dataseta set of records used for analysisMedium
12distributionthe way values are spread across a groupMedium
13experimenta planned test of an ideaMedium
14factora condition that can influence a resultMedium
15findingan outcome discovered through investigationMedium
16frequencyhow often something happensMedium
17generateto produce something through a processMedium
18isolateto separate one factor for close studyMedium
19indicatora sign or measure of a conditionMedium
20conductto carry out a study or other organized activityMedium
21methoda planned way of doing somethingMedium
22modela simplified representation of a systemMedium
23monitorto watch or measure over timeMedium
24objectivebased on evidence rather than personal preferenceMedium
25observationinformation gathered by watching or measuringMedium
26parametera value or boundary defining a systemMedium
27patterna repeated arrangement or trendMedium
28percentagea number expressed out of one hundredMedium
29precisionhow closely repeated measurements agreeMedium
30procedurean ordered set of actionsMedium
31ratioa relationship between two amountsMedium
32replicateto repeat a study or result under similar conditionsMedium
33samplea selected part of a larger groupMedium
34scalea range or system used for measuringMedium
35surveyquestions used to collect information from peopleMedium
36trenda general direction of changeMedium
37variablea feature that can take different valuesMedium
38verifyto check whether something is trueMedium
39volumean amount of space or materialMedium
40yieldthe amount produced by a processMedium

Self-check: match the meaning

Cover the table above. Here are 8 of the 40 research and data words, starting with abstract: choose the word each definition describes.

  1. a short summary of a research work
    1. abstract
    2. factor
    3. percentage
    4. survey
    Show answer

    A. abstract

  2. to assign labels to information for analysis
    1. indicator
    2. code
    3. sample
    4. yield
    Show answer

    B. code

  3. a set of records used for analysis
    1. objective
    2. verify
    3. dataset
    4. category
    Show answer

    C. dataset

  4. how often something happens
    1. precision
    2. assess
    3. database
    4. frequency
    Show answer

    D. frequency

  5. a planned way of doing something
    1. method
    2. scale
    3. correlate
    4. finding
    Show answer

    A. method

  6. a value or boundary defining a system
    1. volume
    2. parameter
    3. experiment
    4. conduct
    Show answer

    B. parameter

  7. a relationship between two amounts
    1. baseline
    2. isolate
    3. ratio
    4. observation
    Show answer

    C. ratio

  8. a general direction of change
    1. criteria
    2. monitor
    3. procedure
    4. trend
    Show answer

    D. trend

Using research and data words on the test

  • In Listen to an Academic Talk, a speaker may define baseline or dataset on the spot; note the definition, not just the word.
  • In Read an Academic Passage, isolate and observation often carry a paragraph's main point, so check how each one connects to the sentence before it.
  • In Complete the Words you see only the first letters of a word, so practice spelling replicate and volume as well as knowing what they mean.

Other medium themes

Frequently Asked Questions

40, from abstract to yield, all in the medium tier of our TOEFL list. The self-check quiz on this page tests 8 of them, beginning with abstract.

Language like this is most useful in Listen to an Academic Talk, Read an Academic Passage and Complete the Words. These are general academic words worth recognizing quickly and using when they fit.

Start with code (to assign labels to information for analysis); frequency (how often something happens); parameter (a value or boundary defining a system). In Listen to an Academic Talk, a speaker may define baseline or dataset on the spot; note the definition, not just the word.

Related Resources