weedy

1. (botany) Characteristic of a plant that grows rapidly and spreads invasively, and which grows opportunistically in cracks of sidewalks and disturbed areas.Examples: "a weedy species"; "a weedy vine"; "[…] and so your soyle being drayned and kept dry, all those wéedy kindes of grasse will soone perish."

2. (figurative, of a person or animal) Small and weak.Examples: "a weedy lad"; "I’ll bring Grace, who is looking rather pale and weedy; growing too fast, I’m afraid."; "1924, Edith Wharton, The Spark (The Sixties), Chapter 2, in Old New York, New York: 1981, p. 146, Byrne was hurling himself across the field, crouched on the neck of his somewhat weedy mount […]"Synonyms: scraggy, ungainly, angular, anorexic, carrion, emaciated, gangling, ganglyfiguratively

3. (figurative, UK, Ireland, informal) Lacking power or effectiveness.Examples: "a weedy excuse"; "a weedy attempt"; "a weedy motor"Synonyms: feeble, anemic, breakable, broken-down, damaged, debilitated, decrepit, delicateIrelandUKfigurativelyinformal