Of an instrument, mechanical part, etc.: accurately formed, positioned, or aligned; correctly calibrated. Also of a line or something linear…

†(a) (Of an instrument) marked by or adapted to precision (obsolete); (b) (of a natural action, process, etc.) uniform in operation, regular, even…

Of an instrument: exact, accurate.

Of a sense, physical faculty, measuring instrument, etc.: capable of delicate perception or discrimination; sensitive.

Of an instrument: capable of detecting or measuring very slight changes, quantities, signals, etc.; sensitive. Also of a measurement: precise.

Of an instrument or apparatus: capable of showing minute differences; finely poised or adjusted. Obsolete.

Of methods, instruments of research, language, etc.: Characterized by precision, not admitting of vagueness or uncertainty. exact sciences n. those…

In extended use. Of a measuring instrument, substance, etc.: readily affected by physical stimuli or external forces; responsive to or recording…

In various extended uses, of a thing. See also sense A. 5b. Of a measuring instrument: responsive to or recording slight changes of condition…

Possessing or intended to possess exactness of performance, execution, or construction.

Acute, piercing; accurate. Esp. of a visual image or camera: exhibiting high resolution; extremely precise or sensitive.