What was the first slang word?

It's impossible to definitively say what the first slang word was. Slang is a constantly evolving aspect of language, and its origins are often lost to time.

Here's why it's so difficult to pinpoint the first slang word:

* Slang is informal: It's not recorded in official dictionaries or academic texts as meticulously as formal language.

* Slang is regional: What's considered slang in one place might be standard language in another.

* Slang is constantly changing: Words come and go, and meanings shift over time.

However, we can look at some early examples of slang:

* "Cant" - This was a secret language used by thieves and beggars in the 15th and 16th centuries. It could be considered an early form of slang.

* "Vulgar tongue" - This term referred to language considered informal and lower-class, which would have included slang words.

Ultimately, while we can't identify a single "first slang word," it's clear that informal language has existed for centuries, and its use is a natural part of human communication.