adequate for the purpose; enough

sufficient proof; sufficient protection.

Logic . (of a condition) such that its existence leads to the occurrence of a given event or the existence of a given thing. Compare necessary ( def. 4c ) .

Archaic . competent.

adjective

deficient , inadequate , insufficient , lacking , poor , wanting

adjective

acceptable , agreeable , all right * , ample , aplenty , appreciate , comfortable , commensurable , commensurate , common , competent , copious , decent , due , galore , pleasing , plenteous , plentiful , plenty , proportionate , satisfactory , sufficing , tolerable , unexceptionable , unexceptional , unobjectionablenotes:adequate tends toward the qualitative and sufficient toward the quantitative , so adequate is \'suitable to something\' and sufficient is \'enough for something\' , adequate , enough , all right , average , fair , fairish , goodish , moderate , passable , respectable , able , abundant , efficient , equipollent , equiponderant , good , qualified , resourceful , substantial , suffice , valid