The deoxyribose and nitrogen base together form a nucleoside.
Nucleoside=Deoxyribose + Nitrogenous base
The term nucleoside refers to base + sugar
A pentose sugar with the attached Nitrogen base forms a nucleoside
For example,
In DNA,
Nitrogenous base Adenine (A) + deoxyribose = Deoxyadenosine
Deoxyadenosine is a nucleoside which is consists of the base adenine and sugar deoxyribose.