Green’s Dictionary of Slang

(Irish) to run off, to abandon one’s duties, to play truant; thus mitching n. and adj.

[1577		Holinshed Irish Chronicle 7: He was so crost in the nycke of thys determination, that his historie in mitching wyse wandred through sundry hands].
1833		W. Carleton Traits and Stories of Irish Peasantry II 135: I’ll pluck the crow wid you on my return. If you don’t find yourself a well flogged youth for your ‘mitchin’.
1877		‘The Connaught College’ in Laughing Songster 132: You dog, I’ll cut you, how dare you mitche from school!
1884		Western Mail 16 Oct. 3/7: The ‘ossifer’ fails to find his whereabouts for a while, thus he mitches, and in his own phrase ‘has high jinks along with the “nabs” making the dock’.
1907		J.M. Synge Playboy of the Western World Act II: You’re pot-boy in this place, and I’ll not have you mitch off from us now.
c.1914		C. Mac Garvey Green Line and the Little Yellow Road in Mac Thomáis (1982) 158: The top-line double turn, Mick Maguire and Jamesy Byrne, / Were buttys since the days they mitched from school.
1918		K.F. Purdon Dinny on the Doorstep 197: Maybe it’s miching from school you were, all the time!
1937		Taunton Courier 25 Sept. n.p.: ‘Meeching’ — Meech, mitch, mooch, mouch. It can be found in the works of Spenser (1552-1599), Gower (1325-1408), Tusser (1528-1580), Shakespeare (1564-1616) [and] Massinger (1655). Mr Tyrwhitt tells us that in the Promptuarium parvum’ ‘mychyn’ stands as equivalent to ‘pryvely stelyn smale thyngs’. Brielfy, to ‘miche’ is to take or steal small things, to pilfer, and conseuqnetly to lay in wait, to lurk. The boy who clandestinely absents himself from school, is a ‘mitcher’.
1943		(con. 1850s) G.A. Little Malachi Horan Remembers 87: ‘Out on the gur’ = mitching.
1961		(con. 1930s) D. Behan Teems of Times and Happy Returns 87: Mrs Clancey [...] wanted to know why we were home so early from school. ‘I hope yeh weren’t mitching.’.
1977		W. Burrowes Riordans 89: His nine-year old son Christy was to go to court for mitching from school.
1981		(con. 1920s) P. Crosbie Your Dinner’s Poured Out! 220: on the jare mitching.
1994		(con. 1930s) K.C. Kearns Dublin Tenement Life 71: Sometimes we’d go mitching down to where the banana boats would come in and take a few bananas.
1996		D. Healy Bend for Home 32: We wheel right instead of left and go mitching [...] We duck and weave till we’re in a field opposite the school.
2004		(ref. to 1950s) Guardian 9 Feb. 11: My father was told to deliver me to a children’s court [...] The judge said I was there for mitching school.
2015		L. McInerney Glorious Heresies 8: [S]crappers cared little for mitching off school.