Well, work does make me sick.
Dear Word Detective: I was waiting for a call at work yesterday, so I sent an email asking if someone could take a message if I was indisposed. Immediately, I got an email from my older boss asking if I was alright. Puzzled, I looked up “indisposed” in the dictionary and learned that it meant either “ill” or “unwilling.” I’ve always used it as a synonym for “busy.” When I asked my similarly-aged friends, they also thought it meant “busy.” Has the meaning of “indisposed” changed over the span of a generation? — Kate Robinson.
This has turned out to be a very interesting question. My initial reaction was “not that I know of,” but a quick hop, skip and jump through the internet indicates that I might have been a bit hasty, and that “indisposed” does indeed seem to be mutating in an unexpected direction. For the moment, however, it would probably be wise to cease using it to mean “busy” or “tied up,” since to most people it makes you sound either chronically dyspeptic or a bit like Bartleby the Scrivener (whose response to any request, in Herman Melville’s 1856 novella of that name, was “I would prefer not to”).
The root of the adjective “indisposed” is the verb “to dispose,” constructed from the Latin prefix “dis” (apart, away) plus “ponere,” meaning “to place.” The initial sense of “dispose” in English was “to arrange properly,” and this expanded into a variety of senses including “to get rid of” and, more importantly for our purposes here, “to put someone into a favorable mood to do something.” This sense gave us “disposed” meaning “thinking positively about something” or “inclined or willing to do something” (“Larry wouldn’t lend me money, but he was disposed to drive me to the bank”). “Disposed” also has been used since the 14th century in the sense of “in good health.”
“Indisposed” simply tacked the prefix “in” (here meaning “not”) to the front of “disposed” and first appeared in print in English in the early 15th century with the meaning of “not properly put in order; disorganized or unprepared,” in particular with reference to being unprepared for death (a sense now, thankfully, obsolete). Several other senses, also now obsolete, developed in the 15th century, including “of an evil disposition.” By the early 17th century, however, we had developed the two modern senses of “indisposed,” that of “mildly unwell” (“To take the indispos’d and sickly fit, for the sound man,” King Lear, Shakespeare, 1608) and “unwilling or averse to” (“Hardhearted, and indisposed unto Acts of bounty,” 1665).
The emerging use of “indisposed” to mean “busy” or “unavailable” seems to be an extension of the long-standing use of “indisposed” as a euphemism employed in cases where the truth would be either embarrassing (the person is in the bathroom, for instance) or socially offensive (the person simply doesn’t wish to see or talk to you). The fact that “indisposed” is a fairly snooty-sounding word has also lent to its use as a sarcastic or humorous euphemism for being drunk, being absent from work for another reason (such as having been fired) and even for being in jail. Such humorous use of “indisposed” is fairly common in films and the more literate TV sitcoms, where the humor usually relies on “indisposed” being a substantial understatement of the seriousness of the actual situation (e.g., the “indisposed” party is dead and stuffed in the closet).
It seems that if a term is used frequently enough in popular culture as sarcasm, folks will sometimes begin to regard it as a simple synonym, which is apparently what is happening with “indisposed.” Rather than being used as a vague excuse, implying temporary illness, for not doing something or talking to someone, it’s now being used to mean simply “busy or unavailable.” Given a few more decades, this may become an accepted use of the word, but for the moment, as the reaction of your boss illustrated, it’s probably better to stick to a simple “tied up.”