The origin of "rasher" is uncertain, but it is probably related to the French "raser" (to cut or shave) which also gave us "raze" (to destroy or obliterate) and "razor." "Rasher" first appeared in English in the late 16th century. Or ...
The word may come from the Danish and/or from the Icelandic "rask" or "roskr" and "roskna" according to some wordsmiths. The phrase "to razzle" which means "to cook meat at or over the fire" may be derived from these old words.
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