Glossary of Linguistic Terms

Morphological Process

Definition: 

A morphological process is a means of changing a stem to adjust its meaning to fit its syntactic and communicational context.

Discussion: 

Most languages that are agglutinative in any way use suffixation. Some of these languages also use prefixation and infixation. Very few languages use only prefixation, and none employ only infixation or any of the other types of morphological processes listed below.

Source: 
125–126, 130