A suffix is a group of letters that is added to the end of a word to create another word.

Most common suffixes are set solid with the preceding word:

NounsVerbsAdjectivesAdverbs
-al (refusal)-ate (hyphenate)-al (autumnal)-ly (bravely)
-ation (damnation)-en (soften)-ful (hateful)    -ward (homeward)
-dom (freedom)-ify (solidify)-less (wordless)    -wise (clockwise)
-ment (enlargement)-ise (advertise)-ive (deliberative)      
-ness (steepness)     -ous (bulbous)      
-ship (mateship)     -(e)y (tasty) 
-type (archetype)   

Exceptions for hyphens with suffixes

A few suffixes use hyphens in particular combinations:

threefold     fivefold   but   3-fold     25-fold [when combined with numerals]

countrywide     statewide     worldwide   but   Australia-wide     Brisbane-wide [when combined with place names]

airborne     foodborne     waterborne   but   vector-borne     mosquito-borne [when less familiar]