1770, "drunk, overcome with grog so as to stagger or stumble," from grog + -y (2). Non-alcoholic meaning "shaky, tottering" is from 1832, originally from the fight ring. Also used of hobbled horses (1828). Related: Groggily; grogginess.
1749, "alcoholic drink diluted with water," supposedly a reference to Old Grog, nickname of Edward Vernon (1684-1757), British admiral who wore a grogram (q.v.) cloak and who in August 1740 ordered his sailors' rum to be diluted. George Washington's older half-brother Lawrence served under Vernon in the Caribbean and renamed the family's Hunting Creek Plantation in Virginia for him in 1740, calling it Mount Vernon. Eventually the word came popularly to mean "strong drink" of any kind. Grog shop "tavern where alcohol is sold by the glass" is from 1790.
adjective suffix, "full of or characterized by," from Old English -ig, from Proto-Germanic *-iga- (source also of Dutch, Danish, German -ig, Gothic -egs), from PIE -(i)ko-, adjectival suffix, cognate with elements in Greek -ikos, Latin -icus (see -ic). Originally added to nouns in Old English; used from 13c. with verbs, and by 15c. even with other adjectives (for example crispy).
<a href="https://www.etymonline.com/word/groggy">Etymology of groggy by etymonline</a>
Harper, D. (n.d.). Etymology of groggy. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/groggy