weak; feeble; delicate; frail; helpless
frail; having a weak constitution; being in poor health
weak-willed; easily pressured; pushover
frail; having a weak constitution; being in poor health
weak force; weak interaction
weak-headed; can't drink much; can't hold one's liquor; can't take one's drink; easily gets drunk
tenderhearted; faint of heart
dim witted; bird-brained; dullard