禅 is the Chinese form of Sanskrit dhyāna (meditation), and went from China to Korea (Seon) and Japan (Zen). 参 here means 'to investigate / engage with', as in 参公案 — working with koans.
usage
Used more broadly in metaphor: 人生如参禅 ('life is like sitting with a koan'). Overlaps with but is narrower than 打坐 (general seated meditation).