Buffalo buffalo Buffalo buffalo buffalo buffalo Buffalo buffalo.

[momeNt]

How is it a a grammatically correct sentence?

https://en.wikipedia.org/wiki/Buffalo_buffalo_Buffalo_buffalo_buffalo_buffalo_Buffalo_buffalo

The sentence is unpunctuated and uses three different readings of the word "buffalo". In order of their first use, these are:

• a. a city named Buffalo. This is used as a noun adjunct in the sentence;
• n. the noun buffalo (American bison), an animal, in the plural (equivalent to "buffaloes" or "buffalos"), in order to avoid articles.
• v. the verb "buffalo" meaning to outwit, confuse, deceive, intimidate, or baffle.

 

[Ayrahvon]

Colourless green ideas sleep furiously.

 

[CZroe]

How is it a a grammatically correct sentence?

Because the word means many things. In this case, it means enough different things that you can make a complete sentence out of that word alone. It uses Buffalo the city in New York, buffalo the animal AKA bison, buffalo the verb meaning "to bully someone," etc.

Buffalo buffalo Buffalo buffalo buffalo buffalo Buffalo buffalo.

IIRC, it means [People who bully] [bully] [Buffalo residents] [who are also bullies] [bully] [bisons] [people from Buffalo] [also bully].

Something like that. I'm lost.

 

[JujuFish]

Because the word means many things. In this case, it means enough different things that you can make a complete sentence out of that word alone. It uses Buffalo the city in New York, buffalo the animal AKA bison, buffalo the verb meaning "to bully someone," etc.

Buffalo buffalo Buffalo buffalo buffalo buffalo Buffalo buffalo.

IIRC, it means [People who bully] [bully] [Buffalo residents] [who are also bullies] [bully] [bisons] [people from Buffalo] [also bully].

Something like that. I'm lost.

It's more like:

Buffalo bison, which are bullied by Buffalo bison, bully Buffalo bison.