c.1200, "kind, sort, variety," from Anglo-French manere, Old French maniere "fashion, method, manner, way; appearance, bearing; custom" (12c., Modern French manière), from Vulgar Latin *manaria (source of Spanish manera, Portuguese maneira, Italian maniera), from fem. of Latin manuarius "belonging to the hand," from manus "hand" (see manual (adj.)). The French word was borrowed by other Germanic languages, e.g. Dutch manier, German manier, Swedish maner.
Meaning "customary practice" is from c.1300. Senses of "way of doing something; a personal habit or way of doing; way of conducting oneself toward others" are from c.1300. Meaning "specific nature, form, way something happens" is mid-14c. Of literature from 1660s. Most figurative meanings derive from the original sense "method of handling" which was extended when the word was used to translate Latin modus "method." Phrase manner of speaking is recorded from 1530s. To the manner born ("Hamlet" I iv.15) generally is used incorrectly and means "destined by birth to be subject to the custom."
A person who is “to the manner born” is one who has acquired genteel tastes and habits by virtue of having been born into a privileged class: “Rachel is charming at dinner parties — as if she were to the manner born.” This expression is sometimes mistakenly rendered as “to the manor born.” The phrase is from Hamlet, by William Shakespeare.