This paper investigates the semantics of the verb בוא in ancient Hebrew. After reviewing some of the scholarship on the semantics of English 'to come', it shows that in many respects biblical בוא differs from 'to come'. Instead, the Hebrew verb means 'motion towards, or into, a defined location'. Moving to a diachronic mode, the paper demonstrates that the fixed distinction in Aramaic between 'to arrive at' (אתי) and 'to enter' (עלל) was introduced into ancient Hebrew as well, under the influence of Aramaic. This process was linked to the introduction of an important new word, נכנס, whose history (internal and external to Hebrew) is traced. Finally, the semantic situation in mishnaic Hebrew is described, once נכנס usurped much of the semantic territory that had belonged to biblical בוא.