prime

B2 · Upper Intermediate Mathematics Technical

adj. describes a number that can only be divided by itself and the number one.

adj. relating to a positive integer greater than one that has no positive integer divisors other than one and itself.

“Seven is a prime number because you cannot divide it by two, three, or four.”

“Encryption algorithms often rely on the mathematical difficulty of factoring the product of two large prime numbers.”

B2 · Upper Intermediate Uncountable noun

n. the time in your life when you are strongest, most successful, or most beautiful.

n. the state or time of greatest vigour, strength, or success in a person's life or a thing's existence.

日本語:盛り※

“The athlete was in his prime when he won the gold medal.”

“Many critics argue that the painter reached her artistic prime during her years in Paris, before her style became more commercial.”

B2 · Upper Intermediate Technical

v. to put a first layer of special paint on a surface before the main paint.

v. to apply a coat of primer to a surface to prepare it for a finished layer of paint or varnish.

“You need to prime the wooden door before you paint it blue.”

“Failure to prime the metal surface correctly will result in the topcoat peeling off within a few months of exposure to the elements.”

C1 · Advanced Technical

v. to put liquid into a pump or engine so that it can start working.

v. to pour liquid into a pump or to supply fuel to an engine to prepare it for operation.

“He had to prime the old water pump before any water would come out.”

“The mechanic explained that you must prime the fuel system manually if the vehicle has been sitting idle for several years.”