0From 05002br 01b 00holy mackerel02b 00 - exclamation of surprise - A blasphemous oath from the same 'family' as goddam and darn it, etc. Holy Mackerel dates back at least 200 years and is one of very many blasphemous oaths with the Holy prefix. Holy Mackerel was almost certainly a reference to Catholics eating fish on Fridays (rather like Holy Cow is a reference to Hindus, and Holy Smoke is a jibe at incense burning and funeral pyres; also Holy Moses - shortened to the rhyming Holy Moley or Holy Moly - the way that the words trip of the tongue is very significant in how these expressions become widely used and adopted, and Holy Mackerel does have a certain ring to it, in a way that Holy Skate, or Holy Cod do not...
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