"theater, house appropriated to dramatic performances," late Old English pleghus; see play (n.) + house (n.).
Entries linking to playhouse
play 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."
house n.
Old English hus "dwelling, shelter, building designed to be used as a residence," from Proto-Germanic *hūsan (source also of Old Norse, Old Frisian hus, Dutch huis, German Haus), of unknown origin, perhaps connected to the root of hide (v.) [OED]. In Gothic only in gudhus "temple," literally "god-house;" the usual word for "house" in Gothic being according to OED razn.
Meaning "family, including ancestors and descendants, especially if noble" is from c. 1000. Zodiac sense is first attested late 14c. The legislative sense (1540s) is transferred from the building in which the body meets. Meaning "audience in a theater" is from 1660s (transferred from the theater itself, playhouse). Meaning "place of business" is 1580s. The specialized college and university sense (1530s) also applies to both buildings and students collectively, a double sense found earlier in reference to religious orders (late 14c.). As a dance club DJ music style, probably from the Warehouse, a Chicago nightclub where the style is said to have originated.
To play house is from 1871; as suggestive of "have sex, shack up," 1968. House arrest first attested 1936. House-painter is from 1680s. House-raising (n.) is from 1704. On the house "free" is from 1889. House and home have been alliteratively paired since c. 1200.
And the Prophet Isaiah the sonne of Amos came to him, and saide vnto him, Thus saith the Lord, Set thine house in order: for thou shalt die, and not liue. [II Kings xx.1, version of 1611]