chronometer
\kruh-NOM-i-ter\
noun
1. a timepiece or timing device with a special mechanism for ensuring and adjusting its accuracy, for use in determining longitude at sea or for any purpose where very exact measurement of time is required.
2. any timepiece, especially a wristwatch, designed for the highest accuracy.
Quotes
Items both functional and beautiful are on display: compasses, scaled models of canoes, nautical atlases, and astrological texts, as well as an astrolabe, octant, and cross-staff. The marine chronometer (above) is a very precise clock made by William Bond & Son, Boston, circa 1860.
-- Nell Porter Brown, "Finding Our Way," Harvard Magazine, March–April, 2015
Origin
Chronometer entered English in the early 1700s from the Greek root chrónos meaning "time," and the New Latin -metrum, which derives from the Greek métron meaning "measure."
Dictionary.com
