Answer
Not a monomial,
It has more than one term.
Work Step by Step
The standard form of a monomial is $ax^k$ where, $a$ is the numerical coefficient, $x$ is the variable, and $k$ is the degree of the monomial.
The given expression is not in the same form as above since it has three terms. It is what is called a trinomial.
Hence, the given expression is not a monomial, it has more than one term.
