double duty
Fulfilling two functions at the same time, as in Our pickup truck does double duty, since it is used for the business and for family outings.
| a screen or mat covered with a dark material for shielding a camera lens from excess light or glare. |
| 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. |