逆さ

さかさ · sakasa · JLPT N2 · na-adj

upside down

Sounds like sack-a-sack-a; 逆 means reverse, so 逆さ means upside down

逆 (gyaku) is the kanji for reverse or opposite. The trailing さ is okurigana, the kana that completes the native Japanese reading sakasa for the same meaning.

逆 — 辶 walk + 屰 (inverted 大 person)
逆 combines the walking radical 辶 with 屰, a pictograph of an upside-down person. The original sense was 'to meet, go against the flow,' as if walking toward someone coming the opposite way. From this it extended to mean 'reverse, contrary, disobey.'

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