| an extraordinary or unusual thing, person, or event; an exceptional example or instance. |
| 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. |
| Thompson (tŏmp'sən, tŏm'-) Pronunciation Key
American-born British physicist who conducted numerous experiments on heat and friction, which led him to discover that heat is produced by moving particles. |