I was reading 2 Nephi 21:8 with my daughter, and she struggled with a few words.  She read,

And the sucking child shall play on the hole of the asp,

Cockatrice

She said, “It says, A-S-P”

I said, “Asp.  Do you know what an ASP is?”

“No.”

I said, “It is a venomous snake.”

“Oh”.  She continued with verse 8.

and the weaned child shall put his hand on the cockatrice’s den.

“What’s a cockatrice?”

“I have no idea.  Let me look it up.”

So, I pulled out Google on my phone, and it came up with a Wikipedia definition.

A cockatrice is a mythical beast, essentially a two-legged dragon with a rooster‘s head.

While I know that this verse is also found in Isaiah, why on earth did Joseph translate this as a mythical animal?