Cases of word usage

1) an animal able to live both on land and in water (amphibian)

2) adapted for both land and water (amphibious)

3) a covered passage, usually with an arched roof, e.g. with shops along one or both sides (arcade)

4) (especially of lenses in spectacles) design for both distant and near vision (bifocal)

5) an instrument with lenses for both eyes, making distant objects seem nearer (binoculars)

6) with one or both eyeballs turned towards the nose (crosseyed)

7) (of a woman or girl) a formal sign of respect (by bending one or both knees) (e.g. to a queen) (curtsy)

8) a curve of two equal parts formed by cutting through both bases of a double cone (hyperbola)

9) causing destruction to both sides (internecine)

10) a piece of glass (or substance like glass) with one or both sides curved, used in spectacles, cameras, telescopes, microscopes and other optical instruments (lens)