megapenny /ˈmɛ.ɡəˌpɛ.ni/ noun2 •(humorous) A million cents. ($10,000)Or megapenny ($10,000) and nanoacre (for measuring chip sizes). — 1997 •(humorous) An indefinite amount of money, implied to be large.A megapenny for your thoughts, please. — 1992 formsmegapennies