The Oxford Thesaurus An A-Z Dictionary of Synonyms - frail adj.

1) See fragile. 2) ailing, unwell, ill, sick, sickly, poorly, thin, skinny, slight, puny, scrawny, wasting or fading away, languishing, infirm, feeble; crippled, consumptive, phthisic: She is too frail to see visitors.