surplice, (kokuji)
畩 is a Japanese-made kokuji that refers specifically to a surplice, a liturgical vestment. Its meaning is narrow and concrete, with no broader conceptual cluster.
畩 is a kokuji created in Japan by combining 田 (field) and 衣 (garment) to represent a surplice, likely a semantic compound referring to a garment worn in the fields or a specific context. The exact historical motivation is uncertain.
A surplice is a garment (衣) worn in the field (田) during religious ceremonies. Picture a priest wearing a white surplice while standing in a rice field.
For けさ, imagine a priest wearing a surplice and saying 'Kesa, I will wear this garment today.' The word 'kesa' sounds like けさ and ties directly to the surplice meaning.