Degree of a polynomial

The degree of a polynomial is the highest degree of its terms when the polynomial is expressed in its canonical form consisting of a linear combination of monomials. The degree of a term is the sum of the exponents of the variables that appear in it. The term order has been used as a synonym of degree but, nowadays, may refer to several other concepts (see ). For example, the polynomial ${\displaystyle 7x^{2}y^{3}+4x-9}$ has three terms. (Notice, this polynomial can also be expressed as ${\displaystyle 7x^{2}y^{3}+4x^{1}y^{0}-9x^{0}y^{0}}$.) The first term has a degree of 5 (the sum of the powers 2 and 3), the second term has a degree of 1, and the last term has a degree of 0. Therefore, the polynomial has a degree of 5 which is the highest degree of any term.

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