Definition of muscle flexing in English:

muscle flexing

noun

  • The action of tensing or contracting one's muscles, especially to display them; (figurative) a show of power or strength.

Origin

Early 20th century; earliest use found in Journal of Philosophical, Psychological and Scientific Methods. From muscle + flexing.

Pronunciation

muscle flexing

/ˈmʌsl flɛksɪŋ/