吃逆[shakkuri] hiccough
悪逆[akugyaku] atrocity
悪逆無道[akugyakumudou] treacherous
可逆[kagyaku] reversible
可逆反応[kagyakuhannou] reversible reaction

逆さ[sakasa] reverse
逆に[gyakuni] conversely
逆らう[sakarau] to go against
逆ポーランド式[gyakupoorandoshiki] reverse Polish notation

遡る[sakanoboru] to go back
遡及[sakkyuu] tracing back
遡源[sakugen] returning to the origin
遡及的[sokyuuteki] retroactive
遡上[sojou] going upstream

遡航[sokou] going upstream
遡求[sokyuu] redemption
遡河魚[sokagyo] anadromous fish (fish that migrates upstream, e.g. salmon)
遡及書誌[sokyuushoshi] retrospective bibliography
遡求権[sokyuuken] right of recourse