A word that has one part derived from one language and another part derived from a different language is etymologically a hybrid word. The most common form of hybrid word in English is one which etymologically has both Latin and Greek parts. Since many prefixes and suffixes in English have Latin or Greek etymology, it is straightforward to tack a prefix or a suffix from one language onto an English word that comes from a different language, thus creating a hybrid word. This mixing of etymology is considered by some to be bad form, but others consider that, since both (or all) parts have entered the English lexicon, it is a simple conflation of two (or more) English words to make a new English word that connotes some thing that these parts clearly indicate, regardless of the history of its parts, and so is well constituted.

Although the prevailing thought is that such word construction is ill-formed, there are hybrid words in common English usage. Some examples of hybrid words are listed below:

• Homosexual - from the Greek prefix homo meaning "same" and the Latin root sex meaning sex
• Hyperactive - from the Greek huper meaning "over" and the Latin activus
• Kilometre - from the Greek khilioi, "thousand", and the Latin metrum, "measure" (but metrum comes the Greek metron)
• Monolingual - from the Greek mono meaning "one" and the Latin lingua meaning "tongue"
• Mormon - It was alleged by Joseph Smith that Mormon comes from the English "more" and the Reformed Egyptian mon meaning "good".
• Neonate - from the Greek neo, "new", and the Latin natus, "birth"
• Polyamory - from the Greek poly meaning "many" and the Latin amory meaning "love"
• Sociology - from the Latin socius, "comrade", and the Greek logos meaning "word", "reason", "discourse"
• Television - from the Greek tele meaning "far" and the Latin video meaning "to see"