To take into one's family through legal means and raise as one's own child.
To take and follow (a course of action, for example) by choice or assent: adopt a new technique.
To take up and make one's own: adopt a new idea.
To take on or assume: adopted an air of importance.
To vote to accept: adopt a resolution.
To choose as standard or required in a course: adopt a new line of English textbooks.
[Middle English adopten, from Old French adopter, from Latin adoptāre : ad-, ad- + optāre, to choose.] a·dopt'a·bil'i·ty n., a·dopt'a·ble adj., a·dopt'er n., a·dop'tion n.
Usage Note: Children are adopted by parents, and one normally refers to an adopted child but to adoptive parents, families, and homes. When describing places, one can use either adopted or adoptive:She enjoys living in her adopted country. Detroit is their adoptive city.