HSPT: Classifications: name the narrowest group
Find the word that doesn't belong by naming the specific group three of the words share, even when all four come from the same topic.
How do you find the odd word out when all four words seem to go together?
Short answer
Name the most specific group that three of the words share. The answer is the word outside that group, even if it shares a broad topic with the rest.
Know first: Everyday word meanings, Common groups such as animals, tools and units
Step 1 of 5
Three words share a group the fourth one misses
An HSPT classification question lists four words and asks which one does not belong. Usually all four come from the same broad topic. Three of them share a narrower group, and the fourth sits just outside it.
Your job is to name that narrow group as precisely as you can. They're all animals doesn't help when every choice is an animal. Three of them are animals that live in water might.
| Group by | Example set | Odd one | Why |
|---|---|---|---|
| What it measures | ounce, pound, ton, gallon | gallon | The others measure weight. A gallon measures volume. |
| Family within a field | trombone, tuba, flute, French horn | flute | The others are brass instruments. A flute is a woodwind. |
| Shape feature | cube, pyramid, prism, sphere | sphere | The others have flat faces. A sphere has none. |
| Kind of writing | fable, myth, legend, biography | biography | The others are made-up stories. A biography is true. |
| Body part type | wrist, elbow, knee, thumb | thumb | The others are joints. A thumb is a finger. |
The odd word almost always shares the big topic. It misses only the narrow group.
Step 2 of 5
Test every word against the group sentence
Worked example: River, stream, pond, creek
Which word does not belong with the other three?
- Ariver
- Bstream
- Cpond
- Dcreek
- 1
Name the broad topic
All four are bodies of water. That fits everything, so it can't pick out one word.
- 2
Narrow it
River, stream and creek are all kinds of flowing water. A pond is still water that sits in one place.
- 3
Check the fit
Exactly three words fit the group sentence, and exactly one doesn't. That's the sign you've found the right group.
- 4
Why the others tempt you
A river is much bigger than a stream or creek, so it can look like the odd one. But size doesn't split the words cleanly: ponds come in every size. Flowing versus still splits them three and one.
Answer
pond. It's the only one that isn't flowing water.
Find the wrong step
A student answers this question: Which word does not belong with the other three? (A) sofa (B) chair (C) bench (D) table
- 1
Notices that all four words are furniture.
- 2
Since furniture fits all four, looks for any other difference and decides benches are often outdoors.
What went wrong
The student jumped to a loose feature instead of narrowing the group. Benches can be indoors too, and a tighter group, things you sit on, fits exactly three words.
- 3
Picks (C) bench.
The fix
Narrow the group: A sofa, a chair and a bench are all things you sit on. A table isn't. The answer is (D) table.
Step 3 of 5
Name the group yourself
Check yourself · Question 1
Which word does not belong with the other three?
Answer: C
Group sentence: Mile, foot and kilometer all measure length. An acre measures area, the size of a piece of land.
Trap answer: kilometer
A real difference that isn't the group
- Why it looks right
- It's the only metric unit in the list, so it stands out at a glance.
- Why it's wrong
- Metric versus customary does split one word off, but kilometer still measures length like mile and foot. The group sentence that fits exactly three is about what each unit measures.
- The right answer
- acre, because it measures area while the other three measure length.
Check yourself · Question 2
Which word does not belong with the other three?
Answer: D
Group sentence: A ballad, an ode and an epic are all kinds of poems. An essay is written in prose.
Check yourself · Question 3
Which word does not belong with the other three?
Answer: C
Group sentence: Whales, dolphins and seals are all mammals. They breathe air and feed their young milk. A shark is a fish.
Common mistake
Picking the word that looks different on the surface, such as the longest word or the only one you don't know well.
- Why it's tempting
- With about 16 seconds a question, surface differences jump out before you've thought about meaning.
- Do this instead
- Ignore spelling, length and how familiar a word feels. Say what three of the words are, then check which word isn't one of those.
Step 4 of 5
What to remember
Remember
- Name the narrowest group that fits exactly three of the words.
- The odd word usually shares the broad topic and misses only the narrow group.
- If more than one word seems to be the odd one, your group sentence needs to be more specific.
Step 5 of 5
Practice on a real question
Use what you just learned on this question, then check the explanation.
In your own words
What narrow group did three words in the practice question share, and what broad topic fit all four?