mugster School slang.
(ˈmʌgstə(r))
[f. mug v.5 4 + -ster.]
One who ‘mugs’ or works hard.
| 1888 Goschen Rectorial Addr. to Students of Aberdeen in Scotsman 1 Feb., Schools and colleges..have invented for this purpose [viz. depreciation of hard intellectual work]..phrases..such as a ‘sap’, a ‘smug’,..a ‘mugster’. |