"style of speech," early 15c., from Latin locutionem (nominative locutio) "a speaking, speech, discourse; way of speaking," noun of action from past-participle stem of loqui "to speak," from PIE root *tolkw- "to speak." Related: Locutionary.
It forms all or part of: circumlocution; colloquium; colloquy; elocution; eloquence; grandiloquence; interlocution; interlocutor; locution; locutory; loquacious; loquacity; loquitur; magniloquence; magniloquent; obloquy; soliloquy; somniloquy; vaniloquence; ventriloquism; ventriloquy.
It is the hypothetical source of/evidence for its existence is provided by: Latin loqui "to speak;" Old Irish ad-tluch- "to thank," to-tluch- "to ask;" Old Church Slavonic tloko "interpretation, explanation."
"utterance, recitation, action of the verb 'say,' " c. 1300, verbal noun from say (v.); meaning "something that has been said" (usually by someone thought important) is from c. 1300; sense of "a proverbial expression, an adage" is attested from mid-15c.
Phrase it goes without saying is attested from 1862 in a French context, used in English and American newspapers from c. 1868 and much complained of at first as without obvious sense.
Ça va sans dire, a familiar French locution, whose English equivalent might be "that is a matter of course," or "that may be taken for granted." But recently it has become the tendency to translate it literally, "that goes without saying," and these words, though originally uncouth and almost unmeaning to the unpractised ear, are gradually acquiring the exact meaning of the French. [Walsh, 1892]
"not in any degree, not at all," Middle English, from Old English na, from ne "not, no" + a "ever." The first element is from Proto-Germanic *ne (source also of Old Norse, Old Frisian, Old High German ne, Gothic ni "not"), from PIE root *ne- "not." Second element is from Proto-Germanic *aiwi-, extended form of PIE root *aiw- "vital force, life, long life, eternity." Ultimately identical to nay, and the differences of use are accidental.
As an adjective, "not any, not one, none" (c. 1200) it is reduced from Old English nan (see none), the final -n omitted first before consonants and then altogether. As an interjection making a negative reply to a statement or question, "not so," early 13c., from the adverb. As a noun, 1580s as "a denial; a negative vote," 1650s as "person who casts a negative vote."
Construction no X, no Y is attested from 1530s (in no peny no pardon). No problem as an interjection of assurance is attested by 1963. No way as a colloquial expression meaning "it can't be done" is attested by 1968 (noway (adv.) "not at all, in no respect, by no means" is from c. 1300). No-knock (adj.) in reference to police raids without permission or warning is by 1970, American English. Phrase no can do "it is not possible" is attested from 1827, a locution of English-speaking Chinese noted 19c. in China, Australia, and the West Coast of the United States.
We repeated our advice again and again, but got no answer but a loud horse-laugh, and their national maxim of No can do: Europe fashion no do in China. ["Reminiscences of a Voyage to and from China," in Paxton's Horticultural Register, London, 1836]