Theme Sufbixes and prefixes

-oid (usually changes nouns into adjectives)

-like (usually changes nouns into adjectives)

-ity (usually changes adjectives into nouns)

-tion/-ion/ation (usually changes verbs into noun)

-logy/-ology (usually class-maintaining, with the word class remaining a noun)

-ant (usually changes verbs into nouns, often referring to a human agent)

Synthetic languages[edit]

Many synthetic languages—Czech, German, Finnish, Latin, Hungarian, Russian, Turkish, etc.—use many endings.
This is a list of roots, suffixes, and prefixes used in medical terminology, their meanings, and their etymologies. Most of them are combining forms in New Latin and hence international scientific vocabulary. There are a few general rules about how they combine. First, prefixes and suffixes, most of which are derived from ancient Greek or classical Latin, have a droppable -o-. As a general rule, this -o- almost always acts as a joint-stem to connect two consonantal roots (e.g. arthr- + -o- + -logy = arthrology), but generally, the -o- is dropped when connecting to a vowel-stem (e.g. arthr- + -itis = arthritis, instead of arthr-o-itis). Second, medical roots generally go together according to language, i.e., Greek prefixes occur with Greek suffixes and Latin prefixes with Latin suffixes. Although international scientific vocabulary is not stringent about segregating combining forms of different languages, it is advisable when coining new words not to mix different lingual roots.
English prefixes are affixes (i.e., bound morphemes that provide lexical meaning) that are added before either simple roots or complex bases (or operands) consisting of (a) a root and other affixes, (b) multiple roots, or (c) multiple roots and other affixes. Examples of these follow:

• 
  undo (consisting of prefix un- and root do)
  
• 
  untouchable (consisting of prefix un-, root touch, and suffix -able)
  
• 
  non-childproof (consisting of prefix non-, root child, and suffix -proof)
  
• 
  non-childproofable (consisting of prefix non-, root child, root proof, and suffix -able)
  

English words may consist of multiple prefixes: anti-pseudo-classicism (containing both an anti- prefix and a pseudo- prefix).
In English, all prefixes are derivational. This contrasts with English suffixes, which may be either derivational or inflectional.