From Latin *iunctus*, the past participle of *iungere* ("to join, to yoke together"). The same root gives English "junction," "join," and "adjunct." In Spanish it evolved both as an adverb (*juntos*, "together") and a preposition (*junto a*, "next to").

Spanish frequently pairs *junto* with *a* to form the preposition *junto a* ("next to / alongside"), which is preferred in writing over the more colloquial *al lado de*. In Latin American Spanish you'll also hear *juntos* used emotionally in song lyrics and speeches to reinforce solidarity — "juntos podemos" ("together we can") is a near-universal rallying phrase across the Spanish-speaking world.