See Also: molecular clock(medicine)
ten-o'clock(medicine)
around-the-clock(dictionary)
four-o'clock(encyclopedia)
Four-o'clock(medicine)
clock(encyclopedia)
o'clock(dictionary)
o'clock(dictionary)
clock(6)(dictionary)
clock(5)(dictionary)

catcall (iou) and molecular clock (medicine)


catcall (iou)



catcall noun & verb. M17.
[from CAT noun1 + CALL noun.]
A. noun.
Hist. A squeaking instrument or kind of whistle used esp. at a theatre to express impatience or disapproval. M17.
A shrill whistle (now usu. with the lips, formerly on the instrument) expressing impatience or disapproval at a theatre, public meeting, etc. M18.
b. verb.
verb trans. Subject to catcalls. L17.
verb intrans. Sound or make a catcall. M18.

molecular clock (medicine)


molecular clock


This term has two separate uses.

1. <molecular biology> The rate of fixation of mutations in DNA and thus times the rate of genetic diversification.

2. <cell biology> A biological system capable of maintaining up a timing rhythm or pulse. All such clocks are thought to be entrained by a natural oscillator such as the diurnal rhythm.