nāu-, Proto-Indo-European root meaning "boat."

It forms all or part of: aeronautics; aquanaut; Argonaut; astronaut; cosmonaut; nacelle; naval; nave (n.1) "main part of a church;" navicular; navigate; navigation; navy; naufragous; nausea; nautical; nautilus; noise.

It is the hypothetical source of/evidence for its existence is provided by: Sanskrit nauh, accusative navam "ship, boat;" Armenian nav "ship;" Greek naus "ship," nautes "sailor;" Latin navis "ship;" Old Irish nau "ship," Welsh noe "a flat vessel;" Old Norse nor "ship."

"to a sickening extent," Latin, literally "to sickness," from ad "to" (see ad-) + nauseam, accusative of nausea (see nausea). Especially of the disgust aroused by wearisome repetition.

1630s, "to feel sick, to become affected with nausea" (intrans.), from nauseat- past-participle stem of Latin nauseare "to feel seasick, to vomit," also "to cause disgust," from nausea (see nausea). Related: Nauseated; nauseating; nauseatingly. In its early life it also had transitive senses of "to reject (food, etc.) with a feeling of nausea" (1640s), also figurative, "to loathe, to reject with disgust." Meaning "to create a loathing in, to cause nausea" is from 1650s. Careful writers use nauseated for "sick at the stomach" and reserve nauseous (q.v.) for "sickening to contemplate."

c. 1600, "inclined to nausea, easily made queasy" (a sense now obsolete), from nausea + -ous. Sense of "causing nausea or squeamishness" is attested from 1610s. For distinction from nauseated see nauseate. Related: Nauseously; nauseousness.

c. 1200, "sound of a musical instrument;" mid-13c., "loud speech, outcry, clamor, shouting;" c. 1300, "a sound of any kind from any source," especially a loud and disagreeable sound, from Old French noise "din, disturbance, uproar, brawl" (11c., in modern French only in phrase chercher noise "to pick a quarrel"), also "rumor, report, news," a word of uncertain origin, replacing Replaced native gedyn (see din).

According to some, it is from Latin nausea "disgust, annoyance, discomfort," literally "seasickness" (see nausea). According to others, it is from Latin noxia "hurting, injury, damage." OED considers that "the sense of the word is against both suggestions," but nausea could have developed a sense in Vulgar Latin of "unpleasant situation, noise, quarrel" (compare Old Provençal nauza "noise, quarrel"). Confusion with annoy, noisome, and other similar words seems to have occurred.

From c. 1300 as "a disturbance; report, rumor, scandal." In Middle English sometimes also "a pleasant sound." In 16c.-17c. "a band or company of musicians." Noises off, as a stage instruction in theater, "sound effects, usually loud and confused, made off stage but to be heard by the audience as part of the play," is by 1908.