mug (up) v.1
(US) to eat or drink heartily, to have a good meal.
|Basket of Chips 369: The private soakers as locks themselves up with the grog, and mugs themselves, alone.|
|Captains Courageous 161: No reg’lar meals fer no one then. ‘Mug-up when ye’re hungry, an’ sleep when ye can’t keep awake.’.|
|Scribner’s Mag. XXIX 498/2: Let Martin and me mug up and get over near the fire to dry out [DA].|
|Und. and Prison Sl.|