Gravel
Middle English: from Old French, diminutive of grave (see grave4).
wiktionary
From Middle English gravel, grauel, from Old French gravele, diminutive of grave(“gravel, seashore”), from Medieval Latin grava, ultimately from Proto-Celtic *grāwā(“gravel, pebbles”) (compare Breton groa, Cornish grow, Welsh gro), from Proto-Indo-European *gʰroh₁weh₂, from *gʰreh₁w-(“to grind”). Compare also Old English græfa(“coal”).
etymonline
gravel (n.)
"stone in small, irregular fragments," early 13c., from Old French gravele "sand, gravel; sea-shore; sandy bed of a river," diminutive of grave "sand, seashore" (Modern French grève), possibly from Celtic *graw- (compare Welsh gro "coarse gravel," Breton grouan, Cornish grow "gravel"), perhaps ultimately from PIE *ghreu- "to rub, grind" (see grit (n.)). Gravel-crusher was World War I slang for "infantryman."