Synonyms for Gravel (same or very similar meaning)
WordNet sense 1 (rock fragments and pebbles):
crushed rock
WordNet sense 2 (cause annoyance in; disturb, especially by minor irritations):
annoy, bother, chafe, devil, irritate, nark, nettle, rag, rile, vex, get at, get to
WordNet sense 3 (be a mystery or bewildering to):
amaze, baffle, beat, bewilder, dumbfound, flummox, get, mystify, nonplus, perplex, pose, puzzle, stick, stupefy
WordNet sense 4 (unpleasantly harsh or grating in sound):
grating, gravelly, raspy, rough, scratchy, rasping
WordNet sense 5 (having an unpleasant sound):
cacophonous, cacophonic
From the ODE community, based on WordNet
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