noun
former member; resigning member
Refers to a person who has withdrawn from or is in the process of leaving a group, club, or organization. Often used in formal or administrative contexts.
退会者は、再入会の際に手数料がかかります。
Former members are charged a fee when rejoining.
今月の退会者は3名でした。
There were three resigning members this month.
脱退者 is similar but often implies leaving a more tightly knit group or a political party, while 退会者 is more common for clubs, societies, or online services.
Compound of 退会 (withdrawal from a group) + 者 (person). The reading is straightforward on'yomi.