Literary or old-fashioned word for 'head'; in modern Japanese あたま is the usual term. Often appears in set phrases or elevated contexts.
彼は深くこうべを垂れた。
He bowed his head deeply.
こうべをめぐらして辺
He turned his head and looked around.
Usually written in kana; the kanji forms 頭 and 首 are rare and may be confused with other readings.
Rare kanji spelling; normally read あたま or かしら.
Rare kanji spelling; normally read くび.
The historical derivation is uncertain; こうべ is a native Japanese word that has been largely replaced by あたま in modern usage.