ソウ, ソ, ゾウ, かつ.て, か.って, すなわち
once, before, formerly, ever, never, ex-
JLPT0 G13 S0 F5000
A depiction of a cooking pot with a steaming basket atop, from which slender wisps of steam arise and figuratively pile upon each other → *once*; *before*; *at one time*; *formerly* (← prior ← prior wisp of steam).
[Full Kanji Etymology List]