opera-glasses

n [pl] small binoculars for use in the theatre （观剧用的）小型双筒望远镜.

open-ended, open-eyed, open-handed, open-handedly, open-handedness, open-heart surgery, open-hearted, open-minded, open-mindedness, open-mouthed, open-plan, open-work, opencast, opener, opening, opening night, opening-time, openly, openness, opera, opera-house, operable, operate, operatic, operatically, operating system, operating-table, operating-theatre, operation, operational, operations room, operative, operator, operetta, ophthalmic, ophthalmic optician, ophthalmologist, ophthalmology, ophthalmoscope, opiate,