Origin of dinkumfrom dialect, dialectal (Lincolnshire), a fair share of work from uncertain or unknown; perhaps
Origin of dinkumOriginally Australian dialectal fair share of work from English dialectal (Lincolnshire and Derbyshire) dincum, dinkum work perhaps akin to English dialectal (Gloucestershire) ding to work perhaps from Middle English ding to work perhaps from Middle English dingen to strike, hammer, thresh ; see ding2.
(comparative more dinkum, superlative most dinkum)
Unknown, possibly from Lincolnshire dialect. First use (as a noun) from 1888.