Sûi-ti̍t
Sûi-ti̍t (垂直; perpendicular) sī chi̍t ê kí-hô-ha̍k ê su̍t-gú. Tī pêng-bīn kí-hô tiong, nā ū chi̍t tiâu ti̍t-soàⁿ kap lēng-gōa chi̍t tiâu ti̍t-soàⁿ sio-kau, nn̄g ê hō͘-siong kīn-oá ê kak-tō͘ nā sio-siâng, chit nn̄g tiâu ti̍t-soàⁿ tiō hō-chò sûi-ti̍t; ah chit-ê kak-tō͘ tiō hō-chò ti̍t-kak.
