Final answer:
PTDY stands for Permissive Temporary Duty. It is authorized time off granted to service members, allowing them to take leave from their regular duties.
Step-by-step explanation:
PTDY stands for Permissive Temporary Duty. It is a term commonly used in the military to refer to authorized time off granted to service members. During their PTDY, service members are allowed to take leave from their regular duties, often for personal or administrative purposes.