fricative

adj. (of a consonant) sounded by friction of the breath in a narrow opening. n. Such a consonant (e.g. F, th). [latin frico rub]

a. Produced by the friction or rustling of the breath, intonated or unintonated, through a narrow opening between two of the mouth organs; uttered through a close approach, but not with a complete closure, of the organs of articulation, and hence capable of being continued or prolonged; -- said of certain consonantal sounds, as f, v, s, z, etc.