Definition of prime
(Entry 1 of 3)
1a
often capitalized
: the second of the canonical hours
b
: the first hour of the day usually considered either as 6 a.m. or the hour of sunrise
3
: the most active, thriving, or satisfying stage or period
in the prime of his life
4
: the chief or best individual or part : pick
prime of the flock, and choicest of the stall— Alexander Pope
5
: prime number
6a
: the first note or tone of a musical scale : tonic
b
: the interval between two notes on the same staff degree
7
: the symbol ′ used to distinguish arbitrary characters (such as a and a′), to indicate a specific unit (such as feet or minutes of time or angular measure), or to indicate the derivative of a function (such as p′ or f′(x)) — compare double prime
8
: prime rate
prime
adjectiveDefinition of prime (Entry 2 of 3)
1
: first in time : original
2a
: of, relating to, or being a prime number — compare relatively prime
b
: having no polynomial factors other than itself and no monomial factors other than 1
a prime polynomial
c
: expressed as a product of prime factors (such as prime numbers and prime polynomials)
a prime factorization
3a
: first in rank, authority, or significance : principal
a prime example
b
: having the highest quality or value
prime farmland
c
: of the highest grade regularly marketed
—used of meat and especially beef
4
: not deriving from something else : primary
prime
verb
primed; priming
Definition of prime (Entry 3 of 3)
3
: to apply the first color, coating, or preparation to
prime a wall
4a
: to put into working order by filling or charging with something
prime a pump with water
b
: to supply with an essential prerequisite (such as a hormone, nucleic acid, or antigen) for chemical or biological activity
primed female mice with estrogen
5
: to instruct beforehand : coach
primed the witness
6
: stimulate
: to become prime
prime the pump
: to take steps to encourage the growth or functioning of something
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MerriamWebster unabridged
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Time Traveler for prime
The first known use of prime was before the 12th century
See more words from the same century