from The American Heritage® Dictionary of the English Language, 4th Edition
- intransitive v. To reach later maturity; grow old.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- v. To grow older; reach maturity.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- v. grow old or older
Back-formation from senescent.(American Heritage® Dictionary of the English Language, Fourth Edition)