サツ

guess, presume, surmise, judge, understand

JLPT3 G4 S14 F477

As per # (scrape) + roof/building → rub a building spotless, eliminating all dirt. *Observe* is an associated meaning (← observe/inspect that which has been cleaned) → *investigate*; *judge*; *estimate*. Also, *be considerate of* and *profound*.

[Full Kanji Etymology List]