playfellow n.

Middle English pleie, from Old English plega (West Saxon), plæga (Anglian) "quick motion; recreation, exercise, any brisk activity" (the latter sense preserved in swordplay -- Old English sweordplegan -- etc.), from or related to Old English plegan (see play (v.)).

By early Middle English it could mean variously, "a game, a martial sport, activity of children, joke or jesting, revelry, sexual indulgence." Of physical things, "rapid, brisk, or light movement," by 1620s.

Meaning "dramatic performance" is attested by early 14c., perhaps late Old English. Meaning "free or unimpeded movement, liberty and room for action," of mechanisms, etc., is from 1650s. The meaning "activity, operation" (1590s) is behind expressions such as in full play, come into play. The sporting sense of "the playing of a game" is attested from mid-15c.; that of "specific maneuver or attempt" is from 1868.

The U.S. slang meaning "attention, publicity" is by 1929. To be in play (of a hit ball, etc.) is from 1788. Play-by-play in reference to running commentary on a game is attested from 1927. Play on words "pun" is from 1798. Play-money is attested from 1705 as "money won in gambling," by 1920 as "pretend money."

"companion, comrade," c. 1200, from Old English feolaga "partner, one who shares with another," from Old Norse felagi, from fe "money" (see fee) + lag, from Proto-Germanic *lagam, from PIE root *legh- "to lie down, lay." The etymological sense of fellow seems to be "one who puts down money with another in a joint venture."

Meaning "one of the same kind" is from early 13c.; that of "one of a pair" is from c. 1300. Used familiarly since mid-15c. for "any man, male person," but not etymologically masculine (it is used of women, for example, in Judges xi.37 in the King James version: "And she said unto her father, Let this thing be done for me: let me alone two months, that I may go up and down upon the mountains, and bewail my virginity, I and my fellows").

Its use can be contemptuous or dignified in English and American English, and at different times in its history, depending on who used it to whom, it has carried a tinge of condescension or insult.

University senses (mid-15c., corresponding to Latin socius) evolved from notion of "one of the corporation who constitute a college" and who are paid from its revenues. Fellow well-met "boon companion" is from 1580s, hence hail-fellow-well-met as a figurative phrase for "on intimate terms."

In compounds, with a sense of "co-, joint-," from 16c., and by 19c. also denoting "association with another." Hence fellow-traveler, 1610s in a literal sense but in 20c. with a specific extended sense of "one who sympathizes with the Communist movement but is not a party member" (1936, translating Russian poputchik).

Fellow-countrymen formerly was one of the phrases the British held up to mock the Americans for their ignorance, as it is redundant to say both, until they discovered it dates from the 1580s and was used by Byron and others.