Green’s Dictionary of Slang

(US) of a thing or situation, excellent, satisfactory; of a person, first-rate, admirable.

1885		‘High School Sl.’ in N.Y. Dispatch 31 May 7: We had a jim-dandy time at the party last night, didn’t we?
1887		Witchita Eagle (KS) 23 Oct. n.p.: Of all the jim dandy backers up he ever seen I am the jim dandiest.
1896		W.C. Gore Student Sl. in Cohen (1997) 20: jim dandy a. Very good. ‘Billy gave a jim dandy translation.’.
1906		C. M’Govern Sarjint Larry an’ Frinds 15: De Sultan’s house was a peach – yes, sorr, a reg’lar jim-dandy, cracker-jack elegant palace.
1915		G. Bronson-Howard God’s Man 362: Suppose we get nailed by the Customs people [...] in their jim-dandy uniforms?
1929		S.J. Perelman in Marschall That Old Gang o’ Mine (1984) 61: Now here is a ‘jim-dandy’ story.
1931		B. Lubbock Bully Hayes 71: Bob Murray, who was a jimdandy swimmer.
1941		J. Stuart Men of the Mountains 154: He said the blue-tick hound was a jim-dandy possum dog [DA].
1953		Kramer & Karr Teen-Age Gangs 149: And even if you’re jim-dandy you still wait years until they’ve finished building.
1963		A.S. Fleischman Venetian Blonde (2006) 255: You could have put together a foolproof, Jim Dandy spook swindle and big con, and you did.
1976		P. Conroy Great Santini (1977) 254: If Hitler had won the war you’d be reading books about what a jolly good fellow Hitler was and how jim-dandy it was that he killed every Jew that ever lived.
1983		J. Ciardi A Second Browser’s Dict. 157: They gave him a jim-dandy hanging.
1991		R.B. Platt Four Arrows Fe-As-Ko 1: I want you to know I’ve been thinking on the past [...] and I think I come up with a jim dandy story for you.
2005		J. Wegryn Funny Thing about Names 118: And a cup of joe will be jim-dandy.