caducous
/kædˈuːkəs/Definitions
1. adjective
Having a limited duration or validity; becoming obsolete or invalid at a specific time.
“The caducous tax laws are being rewritten to simplify the process.”
2. noun
A term used in botany to describe a leaf that falls off at the end of the growing season.
“The caducous leaves of the deciduous tree are a sign of the changing seasons.”