Etymology From Middle English yesterday, yisterday, ȝesterdai, ȝisterdai, from Old English ġiestrandæġ, ġister dæġ, ġestor dæġ, ġeostran dæġ (“yesterday”), by surface analysis, yester- + day. Cognate with Scots yisterday, yesterday (“yesterday”), Saterland Frisian jässendeeg, järsendeges (“yesterday”, adverb), West Frisian justerdei (“yesterday”), Dutch gisterdag (“yesterday”), dialectal German gestertag (“yesterday”), Swedish gårdag (“yesterday”), Gothic 𐌲𐌹𐍃𐍄𐍂𐌰𐌳𐌰𐌲𐌹𐍃 (gistradagis, “tomorrow”, adverb). Compare further Dutch gisteren (“yesterday”), German gestern (“yesterday”).
1
The day immediately before today; one day ago.
Today is the child of yesterday and the parent of tomorrow.
Yesterday was rainy, but by this morning it had begun to snow.
2 more examples
Yesterday, upon the stair / I met a man who wasn’t there / He wasn’t there again today / I wish, I wish he’d go away …1899, Hughes Mearns, Antigonish:
Yesterday / All my troubles seemed so far away / Now it looks as though they're here to stay / Oh, I believe in yesterday1965, Paul McCartney, “Yesterday”, in Help!:
2
Figuratively The past, often in terms of being outdated.
yesterday's technology
The worker of today is different from that of yesterday.
2 more examples
All our yesterdays have lighted fools the way to dusty death.c. 1606 (date written), William Shakespeare, “The Tragedie of Macbeth”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, →OCLC, [Act V, scene v]:
Risk is everywhere. From tabloid headlines insisting that coffee causes cancer (yesterday, of course, it cured it) to stern government warnings about alcohol and driving, the world is teeming with goblins. For each one there is a frighteningly precise measurement of just how likely it is to jump from the shadows and get you.2013 June 22, “Snakes and ladders”, in The Economist, volume 407, number 8841, page 76:
"Europeans need to get to work yesterday and to focus," she says. "They have 5-10 years to stand on their own two feet in terms of conventional defence capabilities."2026 February 16, Katya Adler, Trump's new world order has become real and Europe is having to adjust fast, BBC: