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1. First or highest in rank or importance; main: Our prime consideration is for the children's safety. See Synonyms at chief. See Usage Note at perfect.
a. Highest in quality; excellent: prime real estate.
b. Being the most desired or suitable example of something: a prime candidate for the study.
3. Of or relating to the USDA highest grade of beef, having abundant marbling and usually only sold at restaurants.
4. First or early in time, order, or sequence: the prime action of the drug.
5. Mathematics Of, relating to, or being a prime number.
a. The period of greatest physical and mental robustness: athletes in the prime of their lives.
b. The period of best performance or peak activity: This car is definitely past its prime. See Synonyms at bloom1.
2. Mathematics A prime number.
3. The prime rate.
4. A mark (′) appended above and to the right of a character, especially:
a. One used to distinguish different values of the same variable in a mathematical expression.
b. One used to represent a unit of measurement, such as feet or minutes in latitude and longitude.
5. also Prime Ecclesiastical
a. The second of the seven canonical hours. No longer in liturgical use.
b. The time appointed for this service, the first hour of the day or 6 am.
6. Linguistics See primitive.
7. The first position of thrust and parry in fencing.
v. primed, prim·ing, primes
1. To make ready; prepare: guard dogs primed for attack.
2. To prepare (a gun or mine) for firing by inserting a charge of gunpowder or a primer.
3. To prepare for operation, as by pouring water into a pump or gasoline into a carburetor.
4. To prepare (a surface) for painting by covering with size, primer, or an undercoat.
5. To inform or instruct beforehand; coach.
To become prepared for future action or operation.
prime the pump Informal
To encourage the growth or action of something.

[Middle English, first in occurrence, from Old French, feminine of prin, from Latin prīmus; see per in Indo-European roots. Noun, sense 5, from Middle English, from Old English prīm, from Late Latin prīma (hōra), first (hour), from Latin, feminine of prīmus.]

prime′ly adv.
prime′ness n.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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References in periodicals archive ?
The Tech Offices Portfolio is situated on nearly 60 acres within the primely located Research Triangle Park, which is the largest dedicated scientific research park in the US, featuring more than 250 companies and 50,000 professionals within 22.5 million sq ft of built-out space, said the company in a statement.
Afser, of Primely Avenue, Hodge Hill, spent three years and three months preying on weak customers at the Birmingham New Street branch before she was exposed in 2016.
On Thursday Afser, of Primely Avenue, Hodge Hill, was sentenced to four years in prison at Birmingham Crown Court, after pleading guilty to 19 counts of fraud.