abstruse
Americanadjective
-
hard to understand; recondite; esoteric.
abstruse theories.
- Synonyms:
- arcane, unfathomable, incomprehensible
- Antonyms:
- obvious, simple, uncomplicated, clear
-
Obsolete. secret; hidden.
adjective
Other Word Forms
- abstrusely adverb
- abstruseness noun
Etymology
Origin of abstruse
1590–1600; < Latin abstrūsus thrust away, concealed (past participle of abstrūdere ), equivalent to abs- abs- + trūd- thrust + -tus past participle suffix
Explanation
Abstruse things are difficult to comprehend because they are deep, complex, and intellectually challenging. While a riddle may be a little tricky to figure out, theoretical quantum entanglement is abstruse. The Latin root of the word abstruse is abstrusus, meaning "hidden, concealed, secret," which is a good way to remember the meaning of this word. It describes something so dense or complex that its meaning feels hidden from understanding. A theory or a text is abstruse when it requires deep study to uncover its "hidden" truth. Some famously abstruse topics include high-level mathematics like Category Theory, "the mathematics of mathematics," and certain coding languages, like Malbolge.
Vocabulary lists containing abstruse
300 Most Difficult "SAT" Words
Looking to grow your vocabulary? Check out this interactive, curated word list from our team of English language specialists at Vocabulary.com – one of over 17,000 lists we've built to help learners worldwide!
Frankenstein
Interested in learning more words like this one? Our team at Vocabulary.com has got you covered! You can review flashcards, quiz yourself, practice spelling, and more – and it's all completely free to use!
It's All a Blur: Synonyms for "Unclear"
Want to remember this word for good? Start your learning journey today with our library of interactive, themed word lists built by the experts at Vocabulary.com – we'll help you make the most of your study time!
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
Mr. Barnes has long brought something exotic to English literature, but never anything so abstruse as to become alienating.
From The Wall Street Journal • Jan. 16, 2026
That might sound like an abstruse philosophical argument, but he says it's a hot debate within the scientific community.
From Salon • Jun. 15, 2025
The decades-old concept could explain many things, such as where WIMPs come from, but its main job is to solve a more abstruse problem.
From Science Magazine • Mar. 27, 2024
News articles quoted an effusive Dias and featured photographs of him beaming in triumph in front of a blackboard filled with abstruse scribbles.
From Los Angeles Times • Nov. 10, 2023
At sixteen, he made his way through Bertrand Russell and Alfred North Whitehead’s famously abstruse masterpiece Principia Mathematica.
From "Outliers" by Malcolm Gladwell
![]()
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.