英语词源字典 - 在线词源网站

absolutely (adv.)[absolutely 词源字典]: late 14c., "unconditionally, completely," from absolute (adj.) + -ly (2). From mid-15c. as "without reference to anything else, not relatively;" meaning "to the utmost degree" emerged by mid-16c. As a colloquial emphatic in American English, it is attested from 1892.[absolutely etymology, absolutely origin, 英语词源]
conditional (adj.): late 14c., condicionel, from Old French condicionel (Modern French conditionnel), from Latin conditionalis, from condicionem (see condition (n.)). Related: Conditionally.
unconditional (adj.): 1660s, from un- (1) "not" + conditional (adj.). Related: Unconditionally. Unconditional surrender in the military sense is attested from 1730; in U.S., often associated with Civil War Gen. Ulysses S. Grant and the taking of Fort Donelson.
The ringing phrase of Grant's latest despatch circulated through the North like some coinage fresh from the mint, and "Unconditional Surrender," which suited the initials of his modest signature, became like a baptismal name. [James Schouler, "History of the United States of America," Dodd, Mead & Co., 1899].