Green’s Dictionary of Slang

grease v.3

[grease n.1 (2c)]

(US Und.) to open a safe using nitroglycerine.

[US]Ersine Und. and Prison Sl.
[US]Monteleone Criminal Sl. (rev. edn).
[US]T. Runyon In For Life 196: I learned how to make nitroglycerin [...] and grease a safe with it.