hestiernal (adj.): pertaining to yesterday
hodiernal (adj.): pertaining to today
crastinal (adj.): pertaining to tomorrow (as a tense)

Holy fuck! I can’t believe these words even exist! Granted, they probably haven’t been used since 1846, when Horatio Hale (yes!) used them to describe the 15 tenses (most of which aren’t really tenses so much as tense-aspect combinations) of an aboriginal Australian language he calls Wiradurei (Horatio Hale, “Ethnology and Philology”, p. 494 in Narrative of the U.S. Exploring Expedition, Volume 1 by Charles Wilkes. Philadelphia: C. Sherman, 1846.)

Thing is, I love these words to death and I can’t wait to casually fling them about confusingly (“When did you guys meet up?” “I don’t remember, let me check my hestiernal calendar”), but the more I think about it, the more I can’t think of a phrase in which they’re really necessary. Don’t get me wrong: I’m the last person who would suggest that necessity should be the determinative factor of a word’s existence, value, or cool factor, but I can’t escape the realization that I’ve never needed these words or other signifiers bearing their meaning before now, and I may never need them, crastinally or beyond.

[unceremoniously cribbed from Language Log, "Journalistic Dreamtime," by my hero Mark Liberman. Are boys allowed to have girl-crushes? Is that question too heteronormative to function?]