Spirifer \Spi"ri*fer\, n. [NL., fr. L. spira a coil + ferreto
bear.] (Paleon.)
Any one of numerous species of fossil brachipods of the genus
{Spirifer}, or {Delthyris}, and allied genera, in which the
long calcareous supports of the arms form a large spiral, or
helix, on each side.
[1913 Webster]