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1.
a happy clapper is seriously religious person, most often used in connection with reference to a re-born or new-born christian.

can also be used as a describtion of someone naive or easy to please.
- "what happened to mike? he don't come round to our club no more."

- "well, he don't go out doin sinful things no more. he's a happy clapper now."

- "what? oh man. amen!"

or

"you think i 'm stupid? do i look like a happy clapper to you?!"
by melsugar September 03, 2006