The Collaborative International Dictionary
Encheason
Encheson \En*che"son\, Encheason \En*chea"son\, n. [OF.
enchaison, fr. L. incidere to happen; in + cadere to fall.]
Occasion, cause, or reason. [Obs.]
--Chaucer.
Wiktionary
encheason
n. (context obsolete English) A cause, reason.