Nabi (נָבִיא) is the primary Hebrew word for prophet, appearing about 316 times. The etymology is debated: it may derive from a root meaning "to bubble forth" or "to flow" (describing inspired speech) or from an Akkadian root nabu meaning "to call" or "to announce." The verb form naba (H5012) means "to prophesy."
A nabi was not primarily a predictor of the future — though prediction was sometimes involved — but rather God's covenant spokesman: one called to speak the word of YHWH to the people, especially calling them back to covenant faithfulness.
The prophetic office in Israel was founded with Moses, the supreme prophet (Deut. 18:15, 34:10), and carried forward through a succession of covenant messengers. God's declaration through Moses — "I will raise up for them a prophet like you from among their brothers, and I will put my words in his mouth" (Deut. 18:18) — established both the pattern and the eschatological hope of the Prophet.
The literary prophets (Isaiah, Jeremiah, Ezekiel, the Twelve) formed the canonical prophetic witness, addressing every dimension of national life. Their core message was twofold: covenant accusation (rib) — "You have broken the covenant!" — and eschatological promise — "The LORD will restore!" The New Testament opens with the recognition that Jesus is the fulfillment of the entire prophetic witness (Luke 24:27). He is himself the Word of God spoken definitively (Heb. 1:1-2).