Blimey

google

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late 19th century: altered form of ( God ) blind (or blame ) me!

wiktionary

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A minced oath derived from ( God) blind me (either concurrent with or from a clipping of cor blimey or gorblimey), or blame me. [1] Compare crivvens, drat, etc.

etymonline

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blimey

by 1889, probably a corruption of (God) blind me! First attested in a slang dictionary which defines it as "an apparently meaningless, abusive term."