A grammatical term referring to a prefix, i.e., a morpheme added to the beginning of a word to modify its meaning. Used in linguistic contexts.
"O" and "go" are examples of Japanese prefixes.
Compound of 接 (setsu, 'attach') + 頭 (tō, 'head') + 詞 (shi, 'word' or 'part of speech'), literally 'word attached to the head'. The term is a modern linguistic coinage.