Green’s Dictionary of Slang

dill n.1

also dil
[? dillpot n. (1)/backform. f. dilly adj.1 (1); the late 20C UK use may also be attributed to an abbr. of the comic name Dilbert (slightly transformed by the comedian Lenny Henry into his bumptious character Delbert Wilkins); also note dildo n. (1)]

(Aus./N.Z./US) a fool; also as adj., foolish.

Show quotations
Dly Examiner (Grafton, NSW) 9 May 4/2: When Constable Brown flashed his torch on Harold Anderson [...] and his lady friend [...] while they were seated on the running board of a motor car at night, Anderson called him. ‘a big dill.’ This appellation was resented by the constable.
[Aus]Argus (Melbourne) 10 Feb. 12: Sad Sack, the drip or dill of the US Army.
[Aus]L. Glassop Lucky Palmer 57: Don’t be silly. [...] Don’t be a dill all your life.
[Aus](con. 1936–46) K.S. Prichard Winged Seeds (1984) 189: Never thought I could be such a dill as to cry about any man.
[Aus]‘Nino Culotta’ They’re a Weird Mob (1958) 13: Well don’t stand there like a dill; d’yer wanta beer or dontcha?
[Aus]P. White Solid Mandala (1976) 95: He’s only that ginger dill who serves you with the sugar down at Allwrights!
[Aus]D. Ireland Glass Canoe (1982) 39: You had to be a dill not to know Alky Jack had a mind.
[Aus]T. Winton That Eye, The Sky 112: Get up, Morton Flack, you dill. Get out of the water or you’ll die!
[NZ]McGill Dict. of Kiwi Sl. 36/1: dill silly or incompetent person, possibly from daffodil, where ‘daffy’ means daft.
[Aus]Penguin Bk of More Aus. Jokes 216: Look, my cobber will be in here soon. [...] He’s a bit of a dill. Short of a few kangaroos in the top paddock.
[NZ]McGill Reed Dict. of N.Z. Sl. [as cit. 1988].
[Aus]P. Temple Truth 205: He got the sack a few years ago. The sub-prime crash. Went from being a genius to being a dill in two months.
[US]J. Stahl OG Dad 53: Texas high school quarterbacks. The kind of dils who would have grabbed me in the gym locker, hung me upside down [...] when I was young and Jewy.
[Aus]T. Spicer Good Girl Stripped Bare 62: Cain is remembered for winning three elections before being undermined by ‘a few dills’ and resigning.
[Aus]G. Gilmore Base Nature [ebook] ‘[A] bunch of macho dils desperate to prove how tough they are’.

In compounds

dillbrain (n.)

(Aus./N.Z.) a fool.

Show quotations
[Aus]Sydney Morn. Herald 9 Apr. 3/4: I have no sympathy with ‘dillbrains’ [...] if foolish people are prepared to pay excessive prices for shoddy articles.
[Aus]Sun. Herald (Sydney) 10 Sept. 3s/2: Within a mater of weeks they’re ‘Stinker’ or ‘Dill-brain’ or ‘Four Eyes’ to somebody.
[Aus]D. Maitland Breaking Out 345: You bloody dill-brain! [...] Can’t you do anything right?
[Aus]C. Bowles G’DAY 108: Marshall has his buck's night the night before the wedding. The dillbrains he is with get him on the slops and put him on a train.
[NZ]McGill Dict. of Kiwi Sl. 36/1: dillbrain silly or incompetent person.
[UK]K. Lette Mad Cows 234: You’re nicked, dillbrain.
[NZ]McGill Reed Dict. of N.Z. Sl. [as cit. 1988].