n.1 a small smooth stone worn by the action of water.
2 a a type of colourless transparent rock-crystal used for spectacles. b a lens of this. c (attrib.) colloq. (of a spectacle-lens) very thick and convex.
3 an agate or other gem, esp. when found as a pebble in a stream etc.
Phrases and idioms:
not the only pebble on the beach (esp. of a person) easily replaced. pebble-dash mortar with pebbles in it used as a coating for external walls.
Derivatives:
pebbly adj.
Etymology: OE papel-stan pebble-stone, pyppelripig pebble-stream, of unkn. orig.