Green’s Dictionary of Slang

sweet, delightful, charming.

1851		Bell’s Life in Sydney 12 July 3/1: As for his moustaches, they are [...] ‘duckies‘ and perhaps the most perfect erinegerous adornments that ever graced a biped’s mousetrap.
1868		‘The Stirabout Pot’ in My Young Wife and I Songster 37: Her principal bit of furniture / Was a ducky little stirabout pot.
1880		Bulletin (Sydney) 9 Oct. 2/3: A jaunty little cap, and a pair of the duckiest little shoes.
1889		Dodge City Times (KA) 11 July 3/4: A butter-fly dude of Cimarron calls [...] quite often to see his ducky-jewlarker.
1899		Kipling ‘The Moral Reformers’ in Complete Stalky & Co. (1987) 132: I’m only goin’ to take off one ducky little whisker.
1915		G. De S. Wentworth-James Purple Passion 39: It’s a ducky place [...] Everybody loves it – you’d love it!
1922		Joyce Ulysses 347: Baby looked just too ducky, laughing up out of his gleeful eyes, and Cissy poked him like that out of fun in his wee fat tummy.
1930		H. Ashton Doctor Serocold (1936) 121: All those ducky little islands.
1936		D. Burley in Chicago Defender 4 July 10: So ducky [...] Eleanor Sayre floating past, dancing in the arms of that handsome [...] physish.
1943		R. Chandler Lady in the Lake (1952) 5: Perfumes in little pastel phials tied with ducky satin bows.
1951		Cusack & James Come in Spinner (1960) 244: We’ve got the duckiest little flat at Point Piper.
1960		D. Hamilton Death of a Citizen 76: I saw that the damn little heap [...] had a ducky little miniature air-conditioning unit under the dash.
1970		B. Aldiss Hand-Reared Boy 131: Oh, you’ll look so ducky in nursing uniform.
1984		W.J. Caunitz One Police Plaza 159: Oh, that’s ducky.
1992		Eble Campus Sl. Apr. 3: duckie – in style.
1999		S. Grafton O is for Outlaw (2000) 271: ‘I’m tied up tonight, but how’s Monday. Does that work?’ ‘Sounds ducky.’.
2013		T. Robinson Hard Bounce [ebook] Well, wasn’t that just ducky.