A giant fleet of warships or battle-tanks or something of the sort. Usually seen in alien sci-fi movies or futuristic movies. Several examples in Star Wars
in Star Wars when the Jedi are fighting enemy armadas of space ships driven by droids.
Person 1: hey you're such a bitch / slut / loser / tool / nerd / skank / hoe / freak / fatperson.. etc
Person 2: You mean I'm an armada?!?!
Person 1: yeah, pretty much
Person 2: I'm gonna go die in a rectum now.
Small town in Michigan's thumb area where people ages 16 to 28 drive their 90s or 80s pick up truck with a 25" lift on it, also where people get amusement from painting on a rock
"There are so many trucks here, where are we?"
"I see that rock, we must be in Armada Michigan"
And dying in yo' bed many years from now, would ya be willing ta trade all da days from dis here day ta dat fo' one chance, just one chance, ta come back here as young men an' tell our enemies dat dey may take our lives but dey will never take our freedom ... YUB NUB!