Zara (זָרַע) means to sow seed, to scatter, or to plant. As a noun (H2233, zera), it means seed, offspring, descendants, or posterity. The verbal root appears about 55 times and the noun over 220 times, making "seed" one of the most theologically loaded words in the Hebrew Bible.
Both agricultural and genealogical meanings are active simultaneously in Hebrew thought. To "sow" in a field and to "produce offspring" share the same root because ancient Israelites understood procreation and agriculture through the same conceptual lens of divine provision and covenant continuation.
The "seed" (zera) is a thread running from Genesis to Galatians. The first messianic promise speaks of the "seed of the woman" who will crush the serpent's head (Gen. 3:15 — the protoevangelium). Abraham was promised a zera as numerous as the stars (Gen. 15:5), through whom all nations would be blessed. The Davidic covenant promised a zera on David's throne forever (2 Sam. 7:12).
Paul's explosive argument in Galatians 3:16 hinges on the singular of zera: "It does not say 'seeds,' referring to many, but referring to one, 'And to your offspring,' who is Christ." The entire Abrahamic promise, Paul argues, culminates in one person — Jesus, the seed par excellence. Sowing also becomes a metaphor for the Word of God (the Parable of the Sower) and for resurrection: "what you sow does not come to life unless it dies" (1 Cor. 15:36).