Etymology
Advertisement
Rubicon (n.)

in the figurative phrase cross (or pass) the Rubicon "take a decisive step," 1620s, a reference to a small stream to the Adriatic on the coast of northern Italy which in ancient times formed part of the southern boundary of Cisalpine Gaul. It was crossed by Caesar, Jan. 10, 49 B.C.E., when he left his province to attack Pompey. The name is from Latin rubicundus "ruddy," in reference to the color of the soil on its banks.

Related entries & more 
Advertisement
Egypt 
Old English Egipte "the Egyptians," from French Egypte, from Greek Aigyptos "the river Nile, Egypt," from Amarna Hikuptah, corresponding to Egyptian Ha(t)-ka-ptah "temple of the soul of Ptah," the creative god associated with Memphis, the ancient city of Egypt.

Strictly one of the names of Memphis, it was taken by the Greeks as the name of the whole country. The Egyptian name, Kemet, means "black country," possibly in reference to the rich delta soil. The Arabic is Misr, which is derived from Mizraim, the name of a son of Biblical Ham.
Related entries & more 
Adam 
masc. proper name, Biblical name of the first man, progenitor of the human race, from Hebrew adam "man," literally "(the one formed from the) ground" (Hebrew adamah "ground"); compare Latin homo "man," humanus "human," humus "earth, ground, soil."

The name was also used to signify the evil inherent in human nature (as a consequence of Adam's fall), and other qualities (nakedness, gardening) associated with the biblical Adam. Adam's ale "water" is from 1640s. To not know (someone) from Adam "not know him at all" is first recorded 1784. The pet form of the name in Middle English was Addy, hence Addison; other old pet forms (Adkin, Adcock) also survive in surnames.
Related entries & more