Is swarned a word and what does it mean?

"Swarned" is not a standard English word. It's likely a misspelling of "swarmed", which means:

* To move or gather in a large group, especially in a way that suggests disorder or confusion: *The children swarmed around the ice cream truck.*

* To attack in large numbers: *The locusts swarmed the crops.*

If you meant a different word, please provide more context.