clock

n. timepiece, device for telling time

v. measure time, time; register on a time clock

Circadian Locomotor Output Cycles Kaput, or Clock is a gene which encodes proteins regulating circadian rhythm. The CLOCK protein seems to affect both the persistence and length of the circadian cycle. CLOCK forms part of a basic-helix-loop-helix transcription factor. BMAL-1 dimerizes with CLOCK in vivo and transactivates gene expression of Period and Timeless in drosophila by binding to E-box elements in their promoters. BMAL1-CLOCK also regulates Cryptochrome genes (e.g. Cry1, Cry2) and Period genes (e.g. Per1, Per2, Per3) in mammals. The BMAL-CLOCK complex itself is regulated by the expression of Per and Cry genes.
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A clock is an instrument for measuring and indicating the time. The word "clock" is derived ultimately (via Dutch, Northern French, and Medieval Latin) from the Celtic words clagan and clocca meaning "bell". For horologists and other specialists the term "clock" continues to mean exclusively a device with a striking mechanism for announcing intervals of time acoustically, by ringing a bell, a set of chimes, or a gong. A silent instrument lacking such a mechanism has traditionally been known as a timepiece. In general usage today, however, a "clock" refers to any device for measuring and displaying the time which, unlike a watch, is not worn on the person.
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Clock a device for measuring time. biological clock the physiologic mechanism which governs the rhythmic occurrence of certain biochemical, [more]Clock - Community and Resources

Noun
1. a timepiece that shows the time of day
(hypernym) timepiece, timekeeper
(hyponym) alarm clock, alarm
(part-meronym) clock face, clock dial
(derivation) time
Verb
1. measure the time or duration of an event or action or the person who performs an action in a certain period of time; "he clocked the runners"
(synonym) time
(hypernym) quantify, measure
(hyponym) mistime

(v. t.)
To ornament with figured work, as the side of a stocking.
  

(v. t. & i.)
To call, as a hen. See Cluck.
  

(n.)
The striking of a clock.
  

(n.)
A watch, esp. one that strikes.
  

(n.)
A machine for measuring time, indicating the hour and other divisions by means of hands moving on a dial plate. Its works are moved by a weight or a spring, and it is often so constructed as to tell the hour by the stroke of a hammer on a bell. It is not adapted, like the watch, to be carried on the person.
  

(n.)
A large beetle, esp. the European dung beetle (Scarabaeus stercorarius).
  

(n.)
A figure or figured work on the ankle or side of a stocking.