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obtuse

American  
[uhb-toos, -tyoos] / əbˈtus, -ˈtjus /

adjective

  1. not quick or alert in perception, feeling, or intellect; not sensitive or observant; dull.

    Synonyms:
    dim, slow, boorish, gauche, unobservant, imperceptive, blind, insensitive, tactless, unfeeling
  2. not sharp, acute, or pointed; blunt in form.

  3. (of a leaf, petal, etc.) rounded at the extremity.

  4. indistinctly felt or perceived, as pain or sound.


obtuse British  
/ əbˈtjuːs /

adjective

  1. mentally slow or emotionally insensitive

  2. maths

    1. (of an angle) lying between 90° and 180°

    2. (of a triangle) having one interior angle greater than 90°

  3. not sharp or pointed

  4. indistinctly felt, heard, etc; dull

    obtuse pain

  5. (of a leaf or similar flat part) having a rounded or blunt tip

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

Etymology

Origin of obtuse

First recorded in 1500–10; from Latin obtūsus “dulled,” past participle of obtundere, equivalent to ob- ob- + tūd-, variant stem of tundere “to beat” + -tus past participle suffix, with dt > s

Explanation

The adjective obtuse is good for describing someone slow on the uptake: "Don't be so obtuse: get with the program!" The adjective obtuse literally means "rounded" or "blunt," but when it's used for a person, it means "not quick or alert in perception" — in other words, not the sharpest tool in the shed. It's not just for dull people, but also dull angles: in geometry, an obtuse angle is one that is not so sharp (between 90 and 180 degrees).

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Vocabulary lists containing obtuse

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.

Instead, it delivered a watered-down facsimile of those sounds, that critics called "unremarkable", "obtuse" and "lacking in depth".

From BBC • Jun. 13, 2026

Their simultaneous existence indicates a broader trend toward sheer, glorious stupidity that viewers crave when practically everything is either too polished and boring or wilfully obtuse.

From Salon • Jun. 11, 2026

Ms. Field finds this obtuse, considering America’s actual history.

From The Wall Street Journal • Nov. 2, 2025

From “Civil War” to “Game Night,” Plemons has a knack for playing characters who are doggedly, dangerously obtuse, a key he’s still working in here.

From Los Angeles Times • Oct. 23, 2025

Now, when he was on fire with his Cause, Arthur’s justice seemed bourgeois and obtuse beside him.

From "The Once and Future King" by T. H. White

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