High Quality Content by WIKIPEDIA articles! This is a list of roots, suffixes, and prefixes used in medical terminology, their meanings, and their etymology. There are a few rules when using medical roots. Firstly, prefixes and suffixes, primarily in Greek, but also in 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. Secondly, medical roots generally go together according to language: Greek prefixes go 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.