Synonyms: disconfirming, negative
Definition: not indicating the presence of microorganisms or disease or a specific condition
Usage: the HIV test was negative
Similar words: Gram-negative
Definition: (of bacteria) being of or relating to a bacterium that does not retain the violet stain used in Gram's method
Synonyms: disconfirming, invalidating
Definition: establishing as invalid or untrue
Similar words: unsupportive
Definition: not furnishing support or assistance