Green’s Dictionary of Slang

pete n.1

[peter n.3 (2)/peter n.5 (2)]

1. [1910s–50s] (also pete-box) a safe.

2. [1930s–40s] (US) nitroglycerine, used to open safes.

3. see pete-man

In compounds

pete-box (n.)

see sense 1 above.

pete-busting (n.) [bust v.1 (1a)]

[1950s] (US Und.) safe-cracking.

pete job (n.)

[1910s–20s] safe breaking.

pete-man (n.) (also pete)

[1910s+] (US Und.) a safebreaker.

In phrases

sniff a pete (v.)

[1910s] (US Und.) to crack a safe with explosives.