n. 天文钟, 航海用的精密时计, 精密的时钟

[化] 精密记时计

[医] 记时计

[ noun ]
an accurate clock (especially used in navigation)
<noun.artifact>

Chronometer \Chro*nom"e*ter\, n. [Gr. ? time + -meter: cf. F.
chronom[`e]tre.]
1. An instrument for measuring time; a timekeeper.

2. A portable timekeeper, with a heavy compensation balance,
and usually beating half seconds; -- intended to keep time
with great accuracy for use an astronomical observations,
in determining longitude, etc.

3. (Mus.) A metronome.

{Box chronometer}. See under {Box}.

{Pocket chronometer}, a chronometer in the form of a large
watch.

{To rate a chronometer}. See {Rate}, v. t.