onyx

n [U] stone like marble that has different coloured layers in it, used for ornaments, etc 缟玛瑙: [attrib 作定语] an onyx paperweight 缟玛瑙镇纸.

online, onlooker, only, only that, only too, ono, onomatopoeia, onomatopoeic, onrush, onset, onshore, onside, onslaught, onto, onto (also on to), ontological, ontology, onus, onward, onward(s), oodles, oomph, ooze, op, op (also Op), op art, op-ed, opacity, opague, opal, opalescence, opalescent, opaque, opaquely, opaqueness, OPEC, open, open an account, open cheque, open day,