or

conj.或，或者；不然，否则；或者说，即

optical, optical art, optical illusion, optically, optician, optics, optimal, optimism, optimist, optimistic, optimistically, optimization, optimize, optimum, option, optional, optometrist, opulence, opulent, opus, or else, or rather, or so, oracle, oracular, oral, orally, orang-utan, orange, orange squash, orange-blossom, orange-coloured, orangeade, orate, oration, orator, oratorical, oratorio, oratory, orb,