weak-kneed

Adjective

weak-kneed (comparative more weak-kneed, superlative most weak-kneed)

1. (figuratively) Lacking will power or strength of character; timid.
   • It is incontrovertible that the children grow up into rotten adults, without virility or stamina, a weak-kneed, narrow-chested, listless breed, that crumples up and goes down in the brute struggle for life.1903, Jack London, chapter 5, in The People of the Abyss
   • What these teenagers are weighing is at the very heart of Gandhian philosophy: "His absolute insistence on nonviolence, which young men see as pussyfooted and weak-kneed and — dare I say — feminine and hence not macho enough," says Guha, the biographer.2019 October 2, Lauren Frayer, “Gandhi Is Deeply Revered, But His Attitudes On Race And Sex Are Under Scrutiny”, in NPR
2. Used other than figuratively or idiomatically: see weak, kneed.