Sib"i*lant (?), a. [L. sibilans, -antis, p. pr. of sibilare to hiss: cf. F. sibilant.]
Making a hissing sound; uttered with a hissing sound; hissing; as, s, z, sh, and zh, are sibilant elementary sounds.
n.
A sibiliant letter.
© Webster 1913.