-eroo

American  

1. a suffix that creates familiar, usually jocular variations of semantically more neutral nouns; normally added to monosyllabic bases, or merged with bases ending in -er: flopperoo; smackeroo; switcheroo.

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Etymology

Origin of -eroo

Of unclear origin; perhaps extracted from buckaroo, though this word appears to have been conformed to a preexisting suffix (or word), the stress and final vowel being otherwise unaccounted for