Today is Veterans' day.
Look up the etymology:
c. 1500, "old experienced soldier," from French vétéran, from Latin veteranus... from vetus (genitive veteris) "old, aged, advanced in years; of a former time," as a plural noun, vetores, "men of old, forefathers," from PIE *wet-es-, from root *wet- (2) "year" (source also of Sanskrit vatsa- "year," Greek etos "year," Hittite witish "year," Old Church Slavonic vetuchu "old," Old Lithuanian vetušas "old, aged;" and compare wether).
Vetus has no similarities with old or aged.
How could remember the word?