thin as a reed

• slenderThin and graceful
• wispyThin and insubstantial
• willowyTall, slim, pliant
• gauntLean from deprivation
• frailWeak and breakable

delicate · bony · lanky · svelte · reedy · fragile · slight · wiry · skeletal · emaciated · lithe · spindly · waif · cattail · marsh · swaying · hollow · pale