The Collaborative International Dictionary
To save one's bacon
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.
Bacon beetle (Zo["o]l.), 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.]