Green’s Dictionary of Slang

1. (also dicky-dout) a fool.

1845		W.T. Porter Big Bear of Arkansas (1847) 102: A little raggid orflin Boy, with nobody to patch his close torn behin a makin of a dicky-dicky-dout of himself.
1902		H. Baumann Londinismen (2nd edn).

2. the vagina.

1945		song title in Mess Songs & Rhymes of the RAAF 41: The Hairs on Her Dicky-Die-Do.
1966		Trimble 5000 Adult Sex Words and Phrases.
1970		in E. Cray Erotic Muse (1992) 134: The maid of the mountain, she pees like a bloody fountain / And the hairs of her dicky di do hang down to her knees.
1984		Partridge DSUE (8th edn) 305/2: 20C.
1992		Randolph & Legman Ozark Folksongs and Folklore I 403: Also in ‘The Hog-Eye Man’ itself, where it is Jinny who is in the garden ‘a-pickin’ peas, An’ the hair of her snatch hangin’ down to her knees.’ This last trait is taken from the famous pro-woman British ‘The Hair of Her Dicky-Dido’ song.

3. (N.Z.) the penis.

2003

McGill Reed Dict. of N.Z. Sl.