1. A long metal nail.
2. A sharp-pointed projection along the top of a fence or wall.
3. Any long sharp-pointed object used as a fastener or holder.
4. Sharp point on the sole of shoe worn by athletes; spikes provide greater traction.
5. A long sharp-pointed implement (wood or metal).
6. A transient variation in voltage or current.
7. (Botany) An indeterminate inflorescence bearing sessile flowers on an unbranched axis.

1. To secure with spikes.
2. To bring forth a spike or spikes, as of flowers, such as hyacinths; SYN. spike out.
3. To add alcohol beverages; SYN. lace, fortify.
4. To stand in the way of.

A transient electrical signal of very short duration and usually high amplitude. Compare surge.