由
ユ, ユウ, ユイ, よし, よ.る

wherefore, a reason

JLPT3 G3 S5 F325

A depiction of a long-necked (alcohol) container from the mouth of which liquid contents pass/run through, being poured in a slender arc → *cause*; *origin*; *by means of* (← pour from) → *reason*; *circumstances* → *significance*; *purport*. Compare 酉 and 卣.

[Full Kanji Etymology List]