Remember, 'binomial' in mathematics specifically refers to an expression with two terms.
3x - 2y is a binomial because it has two terms.
'Binomial' does not imply a specific operation; it can be addition, subtraction, etc. a^2 - b^2 is a binomial involving subtraction.
When you hear 'binomial' in math class, it might relate to binomial theorem or coefficients. The binomial theorem simplifies expressions like (x + y)^n.