exact

Precisely agreeing with a standard, a fact, or the truth; perfectly conforming; neither exceeding nor falling short in any respect.

Habitually careful to agree with a standard, a rule, or a promise; accurate; methodical; punctual.

Precisely or definitely conceived or stated; strict.

(algebra, of a sequence of groups connected by homomorphisms) Such that the kernel of one homomorphism is the image of the preceding one.