'To save one's bacon' definitions:

Definition of 'To save one's bacon'

From: GCIDE

Bacon \Ba"con\, n. [OF. bacon, fr. OHG. bacho, bahho, flitch of bacon, ham; akin to E. back. Cf. Back the back side.] The back and sides of a pig salted and smoked; formerly, the flesh of a pig salted or fresh. [1913 Webster]
Bacon beetle (Zool.), a beetle (Dermestes lardarius) which, especially in the larval state, feeds upon bacon, woolens, furs, etc. See Dermestes.
To save one's bacon, to save one's self or property from harm or loss. [Colloq.] [1913 Webster] Bacon