Yesterday

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Old English giestran dæg (see yester-, day).

wiktionary

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From Middle English yesterday, yisterday, ȝesterdai, ȝisterdai, from Old English ġiestrandæġ, ġister dæġ, ġestor dæġ, ġeostran dæġ, equivalent to yester- +‎ day; see there for more. Compare Scots yisterday, yesterday(“yesterday”), Gothic 𐌲𐌹𐍃𐍄𐍂𐌰𐌳𐌰𐌲𐌹𐍃( gistradagis, “tomorrow”, adverb). Compare further Dutch gisteren, German gestern.

etymonline

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yesterday (n., adv.)

Old English geostran dæg; see yester- + day.