Sieve cells (Bot.), cribriform cells. See under Cribriform.
Si"fac (?), n. (Zoöl.) The white indris of Madagascar. It is regarded
by the natives as sacred.
Sif"fle*ment (?), n. [F., a whistling or hissing.] The act of whistling
or hissing; a whistling sound; sibilation. [Obs.] A. Brewer.
Sif"i*let (?), n. [Cf. F. siflet.] (Zoöl.) The six-shafted bird of
paradise. See Paradise bird, under Paradise.
Sift (?), v. t. [imp. & p. p. Sifted; p. pr. & vb. n. Sifting.] [AS.
siftan, from sife sieve. √151a. See Sieve.] 1. To separate with a
sieve, as the fine part of a substance from the coarse; as, to sift
meal or flour; to sift powder; to sift sand or lime.