Wiktionary
fist-pump
alt. 1 The forward thrust of one's fist, as in celebration. 2 The hitting together of two people's fists, as e.g. a greeting. n. 1 The forward thrust of one's fist, as in celebration. 2 The hitting together of two people's fists, as e.g. a greeting. vb. To thrust one's fist forward.