Military abbreviation:
Permanent
Change of
Station.
Any time a military member changes location for more than 180 days. Can be used as a noun: I have a PCS to Hanscom AFB; or as a verb I just PCSed here.
Military members who PCS are reimbursed for relocation expenses, and are allowed to ship an amount of personal belongings commensurate with their rank and marital status. Travel expenses are reimbursed at a lower rate than TDY travel, so it is a common practice to send members TDY enroute to PCS, such that al travel is reimbursed at the lower rate.