Spike n.
 1. A sort of very large nail; also, a piece of pointed iron set with points upward or outward.
 2. Anything resembling such a nail in shape.
    He wears on his head the corona radiata . . . ; the spikes that shoot out represent the rays of the sun.   --Addison.
 3. An ear of corn or grain.
 4. Bot. A kind of flower cluster in which sessile flowers are arranged on an unbranched elongated axis.
 Spike grass Bot., either of two tall perennial American grasses (Uniola paniculata, and Uniola latifolia) having broad leaves and large flattened spikelets.
 Spike rush. Bot. See under Rush.
 Spike shell Zool., any pteropod of the genus Styliola having a slender conical shell.
 Spike team, three horses, or a horse and a yoke of oxen, harnessed together, a horse leading the oxen or the span. [U.S.]