Synonyms for gravel

rock fragments and pebbles (noun)

cause annoyance in (verb)

• annoy
• rag
• bother
• irritate
• rile
• nark
• nettle
• vex
• chafe
• devil

be a mystery or bewildering to (verb)

• perplex
• stick
• get
• puzzle
• mystify
• baffle
• beat
• pose
• bewilder
• flummox
• stupefy
• nonplus
• amaze
• dumbfound