Suffixes are a type of word ending that can be added to the end of a root word to change its meaning. The crossword solutions for the term SUFFIXES are APPENDS (7 letters) and ESTS (4 letters). APPENDS is a verb meaning to attach or add something to the end of something else, which is an apt description of what a suffix does. ESTS is a noun meaning a group of people or things with similar characteristics, which could be used to describe the various suffixes that exist in the English language.