Green’s Dictionary of Slang

full hand n.

[1940s+] (Aus.)

1. (Aus. Und.) a five-year prison sentence.

2. (Aus. Und) a life sentence.

3. (also full house, nap hand) a simultaneous dose of both syphilis and gonorrhoea; but note cite 1958.

4. an infestation of both head lice and body lice.

5. (US milit.) a combination of any varieties of disease.

In phrases

play a full hand (v.)

see under play v.