Yamato kotoba form a fundamental part of the Japanese lexicon, similar to native words (from Old English) in English – while borrowed words are used for many technical terms (particularly kango, as with Latin and Greek in English), or for modern or stylish purposes (mostly gairaigo, as with French in English), much of the core vocabulary and commonly used everyday words are of native origin.

As exhibited in the synonyms yamato kotoba/wago, there are often many synonyms from different origins, usually with differences in usage. Very roughly, kango are generally more formal, often restricted to writing, while yamato kotoba are more casual and more often used in speech, but both types of words are commonly used in both speech and writing.

Yamato kotoba are generally polysyllabic (often three or more syllables), and more closely follow the CV (consonant-vowel, CVCVCV) pattern of Old Japanese. By contrast, kango are often one or two syllables, and more often have terminal consonants, yōon, and long vowels.

Japanese adjectives and grammatical words (notably particles) are also Yamato kotoba.

Katakana is generally not used for yamato kotoba, but can be used for emphasis (especially for mimetic words), and for legibility when spelling out a word.