1) Acerbic 2) Barbed 3) Bristly 4) Having pointy tops 5) High 6) High-pitched 7) Like an anime hairstyle 8) Like some dog collars 9) Like some moussed hair 10) Like some punk hairdos 11) Like some punk hairstyles 12) Peaky 13) Prickly 14) Prone to large fluctuations 15) Sharply irritating 16) Slang for ritualistic 1) Peaky 2) Pointed 3) Prickly 
• (a.) Like a spike; spikelike. • (a.) Having a sharp point, or sharp points; furnished or armed with spikes.
Spik'y adjective 1. Like a spike; spikelike. « These spiky , vivid outbursts of metallic vapors.» C. A. Young. 2. Having a sharp point, or sharp points; furnished or armed with spikes. « Or by the spiky harrow cleared away.» Dyer.
Spiky is slang for ritualistic.