1928 (n.) "tough guy," from Spanish macho "male animal," noun use of adjective meaning "masculine, virile," from Latin masculus (see masculine). As an adjective, "ostensibly manly and virile," attested in English by 1959 (Norman Mailer).
"heavy knife or cutlass," used as a weapon and tool by the Spanish in the Americas, 1590s (in pseudo-Spanish form macheto), from Spanish machete "a chopping knife," probably a diminutive of macho "sledge hammer," alteration of mazo "club," which is probably [Barnhart] a dialectal variant of maza "mallet," from Vulgar Latin *mattea "war club" (see mace (n.1)). An alternative explanation traces macho to Latin marculus "a small hammer," diminutive of marcus "hammer," from a base parallel to that of Latin malleus (see mallet).
used allusively from 1985, in reference to John Rambo, hero of Canadian-American author David Morrell's novel "First Blood" (1972), popularized as portrayed by Sylvester Stallone in the Hollywood movie version (1982), a U.S. Vietnam veteran, "macho and self-sufficient, and bent on violent retribution" [OED]. The family name is an old one in New Jersey and Pennsylvania (where Morrell supposedly first heard it), originally Swedish, sometimes said to represent Swedish place name Ramberget, or to be from French Huguenots who took refuge in Sweden.
late 14c., "male human being; male fish or land animal; one of the sex that begets young," from Old French masle (adj.) "masculine, male, adult," also used as a noun (12c., Modern French mâle), from Latin masculus "masculine, male, worthy of a man" (source also of Provençal mascle, Spanish macho, Italian maschio), diminutive of mas (genitive maris) "male person or animal, male."
Male, matching female, applies to the whole sex among human beings and gender among animals, to the apparel of that sex, and, by figure, to certain things, as plants, rimes, cesuras, screws, joints. Masculine, matching feminine, applies to men and their attributes and to the first grammatical gender; a woman may wear male apparel and have a masculine walk, voice, manner, temperament. [Century Dictionary, 1895]