Final answer:
The correct answer to the question is 'obsolete', which is a 7-letter word meaning extinct or no longer in use.
Step-by-step explanation:
The 7-letter word meaning extinct or no longer in use from the options provided is obsolete. The word 'ancient' is used to describe something very old or from a long time ago, such as in the sense of 'fossil', which refers to ancient remnants of life buried underground. 'Abolished' means formally put an end to (a system, practice, or institution), while 'vanished' means to disappear suddenly and completely. 'Obsolete' specifically refers to something that is out of date, no longer in use, or has been replaced by something newer and more efficient.