Being weak or powerless, lacking strength.(adjective)
Having no special abilities or talents, lacking strengths.(adjective)
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Use "strengthless" in a sentence
"Dee would scream a little, always eyes on the worm, and run slowly, as if strengthless, a panicked smile on her lips."
"He stretched out to gather more, trying to hold it, to capture it as it slipped away, leaving him strengthless as he slid to his knees on the kitchen tiles, toppling into a black velvet void."
"And he came forth from the hall with wearied knees and sat on the threshold of the courtyard; and a dark stupor covered him, and it seemed that the earth reeled round beneath his feet, and he lay in a strengthless trance, speechless."