put是放，on是在……的上面，dog是狗，put on the dog是一句美语俚语，意思是摆架子，耍派头，炫耀，摆阔，炫耀，装腔作势。

【例句】
If I have much money, I will put on the dog.
如果我有很多钱，我会摆阔。

Although he is the richest man in this town, he never put on the dog to show off his money.
虽然他是这个镇上最富有的人，但他从来不装腔作势，炫耀自己多么有钱。