CHRONOSCOPE
chronoscope
(noun) an instrument for accurate measurements of small intervals of time
Source: WordNet® 3.1
Etymology
Noun
chronoscope (plural chronoscopes)
An optical instrument used to measure very small time intervals with precision.
Synonyms
• chronometer
Anagrams
• conchospore
Source: Wiktionary
Chron"o*scope, n. Etym: [Gr. -scope.]
Definition: An instrument for measuring minute intervals of time; used in
determining the velocity of projectiles, the duration of short-lived
luminous phenomena, etc.
Source: Webster’s Unabridged Dictionary 1913 Edition