| extraordinary ray | |
| —n | |
| optics double refraction Compare ordinary ray the plane-polarized ray of light that does not obey the laws of refraction in a doubly refracting crystal | |
| a printed punctuation mark (‽), available only in some typefaces, designed to combine the question mark (?) and the exclamation point (!), indicating a mixture of query and interjection, as after a rhetorical question. |
| a stew of meat, vegetables, potatoes, etc. |