軽薄けいはく (keihaku)

彼かれは軽薄けいはくな男おとこだ

He is a frivolous man.

彼女は私に向かって軽薄にほほえんだ。

She smiled flirtatiously at me.

と、ジョーは下卑た軽薄な調子で言った。

"..." Joe said in a vulgar, flippant tone.

少女たちは軽薄で思慮のない様子で笑った。

The girls laughed giddily.

彼女は軽薄に見えるけど根はとてもまじめな人です.

She seems frivolous, but deep down she's a very serious person.

「見た目めは悪わるくないがちょっと軽薄けいはくそう」な外見がいけんとは裏腹うらはらに、彼女かのじょはいないし、女性じょせいに手てが早はやいワケでもない。

In contrast to his "not bad looks but seems a bit of a dandy" appearance, he didn't have a girlfriend and he wasn't particularly fast with the ladies.