| 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. |
| an extraordinary or unusual thing, person, or event; an exceptional example or instance. |
| sodium dichromate | |
| —n | |
| Also called (not in technical usage): sodium bichromate a soluble crystalline solid compound, usually obtained as red or orange crystals and used as an oxidizing agent, corrosion inhibitor, and mordant. Formula Na2Cr2O7 | |