Noggin
mid 17th century (in the sense ‘small drinking cup’): of unknown origin.
wiktionary
Of uncertain origin; attested since the 1600s (e.g. in The Tincker of Turvey) in several forms including the still-current Irish English form naggin, the rare older Irish, Scottish and Northern English form noggan, used by Jonathan Swift, and the Wexford form nuggeen. [1] [2] Tomás S. Ó Máille and some older dictionaries like Skeat's derive it from Irish naigín, cnaigín, from cnagaire, cnag, [3] [4] but the Oxford English Dictionary argues that Irish naigín and Scottish Gaelic noigean instead derive from English. [1] Compare nog.
etymonline
noggin (n.)
1620s, "small cup, mug," later of the contents of such a vessel, "small drink" (1690s), a word of unknown origin, possibly related to Norfolk dialectal nog "strong ale." OED considers that the similar Celtic words are "no doubt" from English. Informal meaning "head" is attested by 1866 in American English.
