Okay sure.
The terms on the left are: 5x^2, 3x, and 11.
Can I define a term? They are the mathematical objects that when grouped together form an expression.
They can be expressed as the product of a coefficient and a variable raised to a power. (Sometimes the coefficient, or variable, or exponent are simplified away like how the term x can be thought of as 1x^1, the term 3x can the be thought of as 3x^1, and the term 11 can be thought of as 11x^0. So each the terms on the left of that equation can be thought of as: 5x^2, 3x^1, 11x^0 respectively.)