The Collaborative International Dictionary of English v.0.48:
Prime \Prime\, n.
1. The first part; the earliest stage; the beginning or
opening, as of the day, the year, etc.; hence, the dawn;
the spring. --Chaucer.
In the very prime of the world. --Hooker.
Hope waits upon the flowery prime. --Waller.
2. The spring of life; youth; hence, full health, strength,
or beauty; perfection. "Cut off in their prime."
--Eustace. "The prime of youth." --Dryden.
3. That which is first in quantity; the most excellent
portion; the best part.
Give him always of the prime. --Swift.
4. [F. prime, LL. prima (sc. hora). See Prime, a.] The
morning; specifically (R. C. Ch.), the first canonical
hour, succeeding to lauds.
Early and late it rung, at evening and at prime.
Note: Originally, prime denoted the first quarter of the
artificial day, reckoned from 6 a. m. to 6 p. m.
Afterwards, it denoted the end of the first quarter,
that is, 9 a. m. Specifically, it denoted the first
canonical hour, as now. Chaucer uses it in all these
senses, and also in the sense of def. 1, above.
They sleep till that it was pryme large.
5. (Fencing) The first of the chief guards.
6. (Chem.) Any number expressing the combining weight or
equivalent of any particular element; -- so called because
these numbers were respectively reduced to their lowest
relative terms on the fixed standard of hydrogen as 1.
[Obs. or Archaic]
7. (Arith.) A prime number. See under Prime, a.
8. An inch, as composed of twelve seconds in the duodecimal
system; -- denoted by [']. See 2d Inch, n., 1.
Prime of the moon, the new moon at its first appearance.