OLY (/ˌoʊɛlˈwaɪ/ OH-el-WY)[1] is post-nominal letters granted by the World Olympians Association (WOA) to registered athletes who have participated in the Olympic Games. The initiative was launched in 2017, and in 2022, post-nominal title PLY was introduced for Paralympic participants.[2][3]
paralympians_eligible_to_apply_for_ply_post_nominal_title_as_first_recipients_named_2022
was invoked but never defined (see the help page).