Green’s Dictionary of Slang

1. drunk.

1831		Satirist (London) 17 Apr. 7/3: [A]fter a good dinner, and under port influence, it has been whispered about that my Lord Tom was ‘toppy’.
1868		Taunton Courier 19 Aug. 8/5: A man might be either ‘clipped,’ ‘touched,’ [...] ‘toppy’.

2. excessive.

1902		Ade Forty Modern Fables 178: No one should [...] put on any toppy Lugs with Silks and Broadcloth.
2001		K. Sampson Outlaws (ms.) 49: They want eights for it, which is toppy in today’s market.

3. (US) upper-class.

1902		C.L. Cullen More Ex-Tank Tales 187: I conned three well-known toppy bachelors of the old town to help act as judges.
1909		Eve. Star (Wash., DC) 11 Sept. 20/5: A toppy glug with a sword and a feather in his skypiece.
1922		Davenport Democrat and Leader (IA) 28 May 32/2–3: I went goofy over one toppy wally.

4. (US) crazy.

1918

Electrical Experimenter (NY) Mar. 759/3: If I don’t soon have something sensible to work on I’ll go toppy.