Synonyms for Spiky:

adj.

abrasive (adjective)
rough, sharp, cutting.
sharp (adjective)
keen, barbed, pointed, thorny, needle-like, spiny, acute, sharp, pointy, jagged, needle-point, sagittal, spiked, Thistly, bristly, spinous, spear-like, prickly, razor-edged, cutting.
thorny (adjective)
spinous, Thistly, bristly.

n.

irregular, coarse, textured, rugged, ragged, abrasive, rough, uneven. body, bedhead, bald, bushy, balding, bouffant, coiffed, close-cropped, bad hair day. spiky (noun)
high-pitched, peaky, high.

Other synonyms:

Other relevant words:
high, high-pitched, peaky, abrasive, rough.

Usage examples for spiky

  1. For at this point of the story Mrs. Cartwright was standing just outside the salle windows beside the dark spiky shape of a cactus; she had put on a pale- hued wrap, and in the puzzling light and shade she appeared gleaming and straight as the flowering rod of the plant. – The Disturbing Charm by Berta Ruck