sandflyPronunciation: /ˈsan(d)flʌɪ/Definition of sandfly noun (plural sandflies) 1a small hairy biting fly of tropical and subtropical regions, which transmits a number of diseases including leishmaniasis. Subfamily Phlebotominae, family Psychodidae: several genera, in particular Phlebotomus 2Australian/NZanother term for blackfly (sense 2).sandfly in other Oxford dictionaries Definition of sandfly in the US English dictionary