opposable

American  

[uh-poh-zuh-buhl] / əˈpoʊ zə bəl /

adjective

1. capable of being placed opposite to something else.

   the opposable thumb of primates.

2. capable of being resisted, fought, or opposed.

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opposable British  

/ əˈpəʊzəbəl /

adjective

1. capable of being opposed

2. Also: apposable.  (of the thumb of primates, esp man) capable of being moved into a position facing the other digits so as to be able to touch the ends of each

3. capable of being placed opposite something else

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Other Word Forms

• nonopposable adjective
• opposability noun
• opposably adverb
• unopposable adjective

Etymology

Origin of opposable

First recorded in 1660–70; oppose + -able

Example Sentences

The Rwanda trip, Mr. Attenborough says, wasn’t supposed to be about gorillas at all, but rather the opposable thumb, one of the significant characteristics we share with the great apes.

From The Wall Street Journal • Apr. 17, 2026

Unlike Lucy, the Burtele foot kept an opposable big toe, which would have been useful for climbing.

From Science Daily • Nov. 28, 2025

Yet the one species of monkey in the group that lacks opposable thumbs, the marmosets, were less likely to be fooled by the trick because they lacked the same digital frame of reference.

From Salon • Feb. 16, 2024

“A thumb, yes, because the opposable thumb is what differentiates us from beasts.”

From New York Times • Jan. 21, 2024

We have five fingers, including one opposable thumb.

From "Cosmos" by Carl Sagan