If i had a math question and in the sentence it said what does the word pie mean what do i put for the answer

A pie is a baked treat, filled with fruit or other stuff, usually in a round dish with a pastry crust.

Pi is a letter in the Greek alphabet, small letter π and capital letter

In math the small letter π is the circle constant, the ratio of a circle's circumference to its diameter.  In a plane, that ratio is constant no matter the size of the circle.  π = 3.14159...

In number theory π(x) is the prime counting function, the number of primes less than or equal to x.   It has nothing to do with the circle constant.

Capital Pi is used as the product sign.  It's like capital Sigma, the summation sign, expect it means multiply not add:

In your question they're probably referring to π the circle constant, so write pi is the ratio of a circle's circumference to its diameter.

Euler was the greatest, but he chose the wrong constant as the circle constant.  A better value would be what we think of as 2π, the ratio of a circle's circumference to its radius, and the full 360 degrees.