Synonyms of the word 
WEAK-KNEED → IRRESOLUTE
weak-kneed
- adj. (figuratively) Lacking will power or strength of character; timid.
- adj. (literally) Used other than as an idiom: see weak, kneed.
irresolute
- adj. Undecided or unsure how to act.
- adj. Indecisive or lacking in resolution.
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