What is the definition of a combining form in medical terminology?

A combining form in medical terminology is defined as a word root plus a vowel, most commonly the letter 'o.' This combination allows medical terms to be more easily pronounced and connects the roots to suffixes or prefixes. For example, in the term "cardiology," the combining form "cardi/o" consists of the word root "card" (meaning heart) and the combining vowel "o." This structure facilitates the formation of terms that may include additional elements, enhancing clarity and fluidity in medical language.

Other combinations, such as the combination of word roots with prefixes or suffixes, do not constitute a combining form by this definition. Combining forms specifically serve the purpose of linking parts of medical terms for better understanding and pronunciation.