Describing an object or substance with little thickness or width; lacking in density or substance. Can also refer to someone or something being slender or lean in appearance, or to a sound or voice that is not full or robust.
Additionally, it can describe something diluted, weak, or of poor quality, as well as an insufficient amount.
CUT
SLIM LANK RARE LEAN FINE BONY WEAK
SPARE GAUNT WEEDY REEDY PRUNE GAUZY LANKY MINTS
SKINNY SVELTE WATERY DILUTE SPARSE SCANTY NARROW MEAGRE REDUCE THINLY FLIMSY SLIGHT
SLENDER SCRAWNY SPIDERY ASARAIL CAMERON THINOUT MELTOFF FRAGILE TENUOUS
HAIRLINE SLIMDOWN
EMACIATED
LOSEWEIGHT SLENDERIZE
UNDERWEIGHT
UNCONVINCING
UNSUBSTANTIAL