adjective
- capable of being placed opposite to something else: the opposable thumb of primates.
- capable of being resisted, fought, or opposed.
adjective
- capable of being opposed
- 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
- capable of being placed opposite something else
adj.1660s, “capable of being withstood,” from oppose + -able. In reference to human thumbs, from 1833. Related: Opposability.