積
セキ, つ.む, づ.み, つ.もる, つ.もり, か, さか, しゃこ, ずみ, つみ
volume, product (x*y), acreage, contents, pile up, stack, load, amass
JLPT3 G4 S16 F541
As per 責# (pile) + 禾 grain/rice → pile crops → *pile/heap up*; *load*; *accumulate* → *area*; *bulk*; *store*; *save*; *savings* → *intention*; *expectation*; *estimation* (← accumulation of ideas).
[Full Kanji Etymology List]