When unanimous, everybody is of same mind and acting together as an undiversified whole. Many groups consider unanimous decisions a sign of agreement, solidarity, and unity.

In the realm of criminal jury trials, many U.S. states and the federal U.S. system require that verdicts be unanimous.

RE:
a sentence using the word unanimous?

bipartisan: “The two brothers reached a bipartisan agreement on when each of them gets to use the car.” bilateral: “The two countries became bilateral in their problems with food shortages.” unilateral: “Try as the boy might, the decision of his parents grounding him was unilateral.” unanimous: “After many long hours in the conference room the two companies reached a unanimous decision on merging.” monolith: “The young man was amazed at the great detail of the giant monoliths.” monopoly: “For Christmas the boy got the thing he wanted the most, the board game Monopoly.” monogram: “The woman reached in her mailbox to find a letter with an odd looking monogram on it.”