You know this one, for sure: “When is a door not a door? When it’s ajar!”
OK, try this one: “When is ajar not ajar? When it’s not a door!”
Perhaps that requires some explanation, lest I leave you with mouths agape. I was playing poker with some friends last night – real ones, not fictional characters – and one of them, Michelle, observed that you can only use ajar on a door, not anything else. Alex, who seldom misses a turn to burnish his cynical and gruff image, in response produced the sentence “Your mouth is ajar.”
And indeed one may on rare occasion see references to mouth(s) ajar – also window(s) ajar. It’s worth noting that mouths ajar would not be the same as mouths agape, as ajar means “slightly open”.
But what, anyway, has a door’s partial openness to do with jars? Were doors once held open with – or for – mason jars (from Arabic jarrah, earthen vessel)? Indeed not, nor has it anything to do with the door having been jarred, i.e., bumped (a word that comes from onomatopoeia for a harsh sound – physical jarring is actually derivative from sonic jarring), though for a time many people thought so. Rather, this jar comes originally from the Germanic word char.
But that’s not the char that has to do with burning, nor the one that has to do with tea, though both involve chores that a charwoman might do. This char, you see, is related to chore – it’s the char in charwoman, and it referred originally to a turn or a returning; the surviving sense is of an occasional turn of work – a little chore. So a door is ajar because doors swing open and return, and one that is not completely returned is still on the turn: a (a variant of on) jar.
This is a word that requires no more effort than closing a door that’s been left ajar (so close it already!). The act of saying ajar, one might say, leaves the mouth ajar – opened but not returned to shut – and the tongue, too: it touches at the tip on the j and then hangs near the palate but not touching it with the retroflex /r/.
It’s a nice, tidy, even pretty little word – the j in the middle is a little unusual, especially in a word so short; it adds a stylish little swing below and dot above, so much nicer than achar, I’d say. It’s raja backwards, and it makes me think of the Steely Dan album Aja, which has (among others) the song “Peg”: “Peg,” Donald Fagen sings, “it will come back to you.” I guess that peg is what the door closes against. The door swings open, and then shut – every time it goes one way, it will go back, Jack, and do it again (OK, that’s a different song). But of course you can always leave it partially open and let the charwoman close it.