A suffix is a group of letters placed at the end of a word to make a new word. A suffix can make a new word in one of two ways:

  1. inflectional (grammatical): for example, changing singular to plural (dog → dogs), or changing present tense to past tense (walk → walked). In this case, the basic meaning of the word does not change.
  2. derivational (the new word has a new meaning, "derived" from the original word): for example, teach → teacher or care → careful
A suffix goes at the end of a word. A prefix goes at the beginning.

Inflectional suffixes

Inflectional suffixes do not change the meaning of the original word. So in "Every day I walk to school" and "Yesterday I walked to school", the words walk and walked have the same basic meaning. In "I have one car" and "I have two cars", the basic meaning of the words car and cars is exactly the same. In these cases, the suffix is added simply for grammatical "correctness". Look at these examples:

suffix grammatical change original word suffixed word
-s plural dog dogs
-en plural (irregular) ox oxen
-s 3rd person singular present like he likes
-ed past tense
past participle
work he worked
he has worked
-en past participle (irregular) eat he has eaten
-ing continuous/progressive sleep he is sleeping
-er comparative big bigger
-est superlative big the biggest

Derivational suffixes

With derivational suffixes, the new word has a new meaning, and is usually a different part of speech. But the new meaning is related to the old meaning - it is "derived" from the old meaning.

We can add more than one suffix, as in this example:

derive (verb) + ationderivation (noun) + alderivational (adjective)

There are several hundred derivational suffixes. Here are some of the more common ones:

suffix making example
original word
suffixed word
-ation nouns explore
-sion persuade
-er teach teacher
-cian music musician
-ess god goddess
-ness sad sadness
-al arrive arrival
-ary diction dictionary
-ment treat treatment
-y jealous
-al adjectives accident accidental
-ary imagine imaginary
-able tax taxable
-ly brother brotherly
-y ease easy
-ful sorrow
-ly adverbs helpful helpfully
-ize verbs terror
-ate hyphen hyphenate
Note that the suffix -er can convert almost any verb into the person or thing performing the action of the verb. For example: a teacher is a person who teaches, a lover loves, a killer kills, an observer observes, a walker walks, a runner runs; a sprinkler is a thing that sprinkles, a copier copies, a shredder shreds.