early 15c., "to cover or wrap (something) to conceal or protect," perhaps from Old French moufle "thick glove, mitten;" see muff (n.). Compare Old French enmoufle "wrapped up;" Middle French mofler "to stuff." The meaning "wrap something up to deaden sound" is recorded by 1761. Related: Muffled; muffling. Muffled oars have mats or canvas about their shafts to prevent noise from contact with the oarlocks while rowing.
"thing that muffles," 1560s, from muffle (v.). Originally "a muffler" (in the old sense), "a wrap for the lower face and neck." Meaning "a cover or wrap used to deaden sound" is by 1734.
1530s, "a kind of wrap or scarf for the throat and lower part of the face," agent noun from muffle (v.). Mechanical sense of "any device used to deaden sound" is by 1856; specifically as "automobile exhaust system silencer" it is attested from 1895.
1917, noun, verb, and adjective, from French camoufler, Parisian slang, "to disguise," from Italian camuffare "to disguise," which is of uncertain origin, perhaps a contraction of capo muffare "to muffle the head." Probably altered in French by influence of French camouflet "puff of smoke, smoke puffed into a sleeper's face" (itself of unknown origin) on the notion of "blow smoke in someone's face." The British navy in World War I called it dazzle-painting.
Since the war started the POPULAR SCIENCE MONTHLY has published photographs of big British and French field pieces covered with shrubbery, railway trains "painted out" of the landscape, and all kinds of devices to hide the guns, trains, and the roads from the eyes of enemy aircraft.
Until recently there was no one word in any language to explain this war trick. Sometimes a whole paragraph was required to explain this military practice. Hereafter one word, a French word, will save all this needless writing and reading. Camouflage is the new word, and it means "fooling the enemy." [Popular Science Monthly, August 1917]