[the ‘Oxford -er’ sfx appeared ‘early in the Queen’s [i.e. Victoria] reign’ (Ware) or was ‘introduced from Rugby School into Oxford University slang, orig. at University College, in Michaelmas Term, 1875’ (OED). The absence of any such terms from the seminal (and slang-laden) Oxford novel The Adventures of Mr Verdant Green (1853, by ‘Cuthbert Bede’) makes the later date far more likely. Strictly jargon, given its use at Oxford, it has moved into wider areas, typically fresher, a university freshman, footer, football, soccer, football and rugger, rugby. The extreme uses, e.g. pragger-wagger, the Prince of Wales and wagger-pagger-bagger, a waste-paper basket remain strictly Oxford and 1900s–20s Oxford at that. For a fuller discussion see M. Marples, University Slang (1950); inter alia he suggests the importation came not from Rugby but from Harrow, seemingly attested by cite 1863 at footer n.2 (1)]
[late 19C+] used to create slangy formations of nouns by shortening the original noun and replacing the missing letters with -er. When the word is a monosyllable, this can be extended by the sfxs -agger or -ugger.