Mat 11:16 To what shall I compare this generation? It is like children sitting in the markets, and calling unto their fellows,
Mat 11:17 And saying, We have piped to you, and you did not dance; we have wailed to you, and you have not lamented.

This is one of my favorite verses whereby Christ describes the inherent flaws of society. Whenever Christ talks about "this generation," his statements can alway be taken as a general indictment of society, then and now.

"Compare" is homoioô, which means "to be made like" "to compare," and "to liken."

"Generation" is genna, which means "descent," "birth," and "origin." It also means "race," "creature," and "family."

"Children" is paidarion, which means "little boy" and "little girl." It is not the word usually translated as "children" in the New Testament which is usually the noun meaning "son," for example, "children of God" is usually huios (sons) theos (God).

"Market" is agora, which is any assemblage of people, a place where people gather, a market or a street.

"Fellows" is hetairos, which means "comrade," "companion," and, in this context of children, "playmate."

"Dance" is orcheomai, which means "to dance," "to leap," and meant going through specific planned steps with a group, not the freeform dancing we know today.

"Wailed" is thrêneô, which means "to sing a dirge," "to deplore," and "wail."

"Lamented" is koptô, which means "to smite," "to pound," and "to beat one's breast."

The general sense of this verse is that when society calls the tune, it expects everyone to follow it. Those who don't follow along, like John, are called out for it.

Another translation of these verses might be:
"How shall I liken you creatures? You are like little kids sitting in a crowd, calling to your playmates: I have played for you and you didn't jump. I have cried at your and you didn't beat your breast."