Beelzebub’s Tales About His Second Descent on to the Planet Earth—p184 notes

Occasion

occasion (n.) “opportunity; grounds for action or feeling; state of affairs that makes something else possible; a happening, occurrence leading to some result,” from Latin occasionem, past participle of occidere “fall down, go down,” from ob “down, away” (see ob-) + -cidere, combining form of cadere “to fall” (from PIE root *kad- “to fall”). The notion is of a “falling together,” or juncture, of circumstances.