50 Essential ISEE & ERB Vocabulary Words Every Middle Schooler Should Know

Big middle school standardized tests like the ISEE (Independent School Entrance Exam) and CTP (aka the ERBs) put a student’s vocabulary skills under the microscope. Some questions require knowledge of absolute vocabulary, like Synonyms and Antonyms, while other questions offer more context, like Sentence Completions. Part of honing those skills across the board? Good old fashioned vocabulary practice. 

At Mulholland Prep, we’ve worked with these tests for years, and along the way we’ve compiled long lists of words that are super helpful for students to expand their knowledge. Here are 50 must-know vocabulary words to jumpstart your student’s prep.

1. Abundant – Having a ton of something; more than enough.
2. Adhere – To stick to something (like glue) or to follow a set of rules.
3. Alacrity – Being super quick and happy to help out.
4. Ambivalent – Having mixed feelings; feeling “stuck” between two choices.
5. Anomaly – Something weird or different that doesn’t fit the normal pattern.
6. Apathetic – Not caring at all; having no interest or “meh” feelings.
7. Arrogant – Thinking you are much better or more important than everyone else.
8. Augment – To add to something to make it bigger or better.
9. Banal – Boring because it’s so common or unoriginal.
10. Belligerent – Ready to fight; acting angry or like a bully.
11. Benevolent – Kind, friendly, and wanting to do good things for others.
12. Capricious – Changing your mood or mind suddenly for no reason.
13. Conspicuous – Super easy to see; standing out in a crowd.
14. Curtail – To cut something short or put a limit on it.
15. Cynical – Distrustful; thinking people are only being nice to get what they want.
16. Deter – To talk someone out of something or discourage them from acting.
17. Diligent – Working really hard and being very careful to do a good job.
18. Dogmatic – Being bossy about your opinions, acting like they are the only “facts.”
19. Dubious – Doubtful; feeling like something is “fishy” or not quite right.
20. Elucidate – To make something clear or explain it so it’s easy to understand.
21. Enigma – A total mystery or a puzzle that is hard to solve.
22. Ephemeral – Lasting for only a very short time (like a bubble or a sunset).
23. Exacerbate – To take a bad situation and make it even worse.
24. Fabricate – To make something up or “craft” a lie.
25. Frivolous – Silly; not having any real purpose or value.
26. Gregarious – Loving to be around people; being very social.
27. Gullible – Easy to trick; believing anything you are told without proof.
28. Hinder – To get in the way or slow someone down.
29. Impetuous – Doing things too fast without thinking about what might happen.
30. Indifferent – Not leaning one way or the other; you just don’t care.
31. Inevitable – Definitely going to happen; you can’t stop it.
32. Innocuous – Harmless; something that won’t hurt or offend anyone.
33. Lethargic – Feeling super sleepy, slow, and having no energy.
34. Lucid – Clear and very easy to understand.
35. Meticulous – Being extremely careful about every tiny detail.
36. Mitigate – To make something less painful, serious, or scary.
37. Novel – Something brand new, original, or unusual.
38. Objective – Looking at just the facts without letting your feelings get in the way.
39. Obscure – Hard to see or hidden away; not well-known.
40. Opaque – You can’t see through it (like a solid wall).
41. Peculiar – Strange, odd, or unique.
42. Pessimistic – Always expecting the worst to happen.
43. Placid – Calm, peaceful, and not easily upset.
44. Plausible – Something that could be true; it sounds believable.
45. Prudent – Being wise and thinking ahead to make good choices.
46. Resilient – Able to “bounce back” quickly after a hard time.
47. Superfluous – Extra; way more than what you actually need.
48. Trivial – Not important; tiny details that don’t really matter.
49. Vague – Not clear; blurry or hard to understand.
50. Zeal – Having huge energy and excitement for a goal.

For more advanced strategies and access to our full database of thousands of practice problems, check out How to Make Vocab Practice Actually Fun and explore our bank of full-length practice tests on our PEAK Platform.