旦 danna (husband)

Let's think of the line as a prone body. My danna is useless! He just lies down all day under the sun , working on his TAN.

husband ★★☆☆☆ 1/2 KANA

the more informal, spoken word for husband (your own or other peoples') - (BOOBOO: if you're talking about someone else's man, say お旦那さん (more polite!))

once you've started to do xxx . . . ★☆☆☆☆ KANA
一 (one) + 旦 (danna (husband)) = 一旦 (once you've started to do xxx . . .)

once you've started to do xxx . . . (i.e. once you've gotten married, you can't get divorced! once you've promised, you can't go back on it!)