What “Nyam” means
Nyam means to eat. It's one of the oldest words in Patois and works like any verb: mi a nyam (I'm eating), dem done nyam (they've finished eating). "Dis nyam!" can also mean the food is delicious.
Examples
Come nyam yuh dinna
Come and eat your dinner.
Wi nuh nyam pork
We don't eat pork.
Dis nyam!
This is delicious
How to use it
Used everywhere, at home, at the cookshop and among friends. It's everyday language, though people may say "eat" in more formal settings.
Where it comes from
From West African languages, which have similar words for "eat" (for example in Twi and Wolof).