sixth (adj., n.)

"next in order after the fifth; an ordinal numeral; being one of six equal parts into which a whole is regarded as divided;" late 14c., replacing by 16c. Middle English sixte (c. 1200), from Old English syxte, from siex (see six). Compare Old Frisian sexta, Middle Dutch seste, Old High German sehsto, German sechste, Gothic saihsta. With ending conformed to -th (1). Related: Sixthly.

The noun meaning "a sixth part" is from 1550s. As a music tone a sixth degree above or below a given tone," especially the sixth tone from the bottom of a scale, by 1590s.

Sixth sense "supernatural perception of objects" is attested from 1712:

Then said Peter, That is false; for there is a sixth Sense, that of Prescience : for the other five Senses are capable only of Knowledg ; but the Sixth of Foreknowledg ; which Sense the Prophets had. [William Whitson, "Primitive Christianity Reviv'd," vol. v, London, 1712]

Earlier it meant "titillation, the sense that apprehends sexual pleasure" (1690s, from Scaliger).

updated on November 23, 2022