1.Monomial- having only one term. For example
2.Binomial- having two terms indicated by + and/or - symbol.For example
3.Trinomial-having three terms indicated by + and/or - symbol. For example
4.Multinomial-having more than 3 terms indicated by + and/or - symbol. For    example:
   2x+2xy+2xyz-3sd, a+b+c+d+e, q+w+e+r+t+y+u,
Note: Even if there is multiplicarion and division involved, it is considered as only one term. For example, 2(x) which is also equal to 2x; it is just one term.

This is my answer hoping that it would help you,it is always a pleasure to help.

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Sorry for the mistake in the NOTE: it is not multiplicarion it is multiplication