Obs. Also 5 calioun, 5–6 calyon. [Of uncertain etymology. Cf. obs. F. caillon ‘a dot, clutter, clot, or congealed lumpe of flegme, bloud, etc.’ (Cotgr.), app. f. cailler to coagulate, curdle, clot (:—L. coagulāre).] A flint nodule; a boulder or pebble; often collective.
c. 1450. Merlin, xx. 329. His horse … ran so swyfte that [? through] the felde that was full of smale caliouns that the fire sparkeled thikke.
1463. in Bury Wills, 37. If … brykke be not sufficient to endure, lete it be maad with calyoun and moorter.
1499. Promp. Parv., 58/2. Calyon, rounde stone, rudus.
1555. Fardle Facions, I. vi. 101. Crickes … whose entringes thenhabitauntes vse to stoppe vp with great heapes of calion and stones.
