It is slang and a suffix that means “-ish/-like“. It is put before a noun, an adjective or a verb.
It is used to say what a person/thing is like. It indicates that a person/thing seems to have a certain character, seems to have a tendency to do something.
Meg is choosing a dress at a clothes shop.
- Meg: I’m going out with Tom tomorrow. What should I wear on my date?
明日トムとデートなの。何着ていこうかな？ - Amy: How about this pink dress?
このピンクの服は？ - Meg: It looks cute except for those cheap looking buttons.
ボタンが安っぽいけど、可愛いね。 - Amy: If you take a closer look, you may feel that it’s a little childish. I think you look great in chick dresses.
よく見ると、少し子供っぽいかも。メグは大人っぽい服が似合うよ。
Ken and Leo are being a couch potato.
- Ken: I got two bags of potato chips for one dollar. Want some chips?
二袋で100ドルのポテチ(orポテトチップス)を買った。食べる？ - Leo: Thanks!
ありがとう！ - Ken: Although they taste cheap and greasy...they’re not as bad as I expected.
安っぽくて、油っぽいけど...思ったほど悪くない。
Amy and her boyfriend have just arrived at the place that they were supposed to be.
- Amy: I just tried calling you but couldn't get through. Did you leave your cell at home?
電話したけど、繋がらなかったよ。携帯、家に忘れてきたの？ - Jim: Yes, I'm sorry. Even I am shocked by how forgetful I am.
うん、ごめん。自分でも驚くほど、忘れっぽいんだよ。