| a gadget; dingus; thingumbob. |
| 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. |
| synchronous converter | |
| —n | |
| a synchronous machine that converts alternating current to direct current, or vice versa | |