sabotage (n.) Look up sabotage at Dictionary.com
1910, from French sabotage, from saboter "to sabotage, bungle," literally "walk noisily," from sabot "wooden shoe" (13c.), altered (by association with Old French bot "boot") from Middle French savate "old shoe," from an unidentified source that also produced similar words in Old Provençal, Portuguese, Spanish, Italian, Arabic and Basque.

In French, the sense of "deliberately and maliciously destroying property" originally was in reference to labor disputes, but the oft-repeated story that the modern meaning derives from strikers' supposed tactic of throwing old shoes into machinery is not supported by the etymology. Likely it was not meant as a literal image; the word was used in French in a variety of "bungling" senses, such as "to play a piece of music badly."
sabotage (v.) Look up sabotage at Dictionary.com
1912, from sabotage (n). Related: Sabotaged; sabotaging.