Green’s Dictionary of Slang

(Aus.) the landlord of a public house.

1881		Adelaide Obs. (SA) 24 Sept. 8/3: What is more to the purpose, there will be Inspectors having the right to scent out bad grog and punish the groggist .
1885		Bulletin (Sydney) 4 Apr. 10/3: The groggist had a lodger, and it occurred to him that, as business was bad, he would go to the races for a week, and leave his friend in charge.