So a kaiju (怪獣) is any kind of big, terrifying, and seemingly undefeatable monster in fiction. The kind we're most familiar with, like Godzilla, are daikaiju (大怪獣) which specifically refers to the giant kind. They vary from being fairly intelligent to being animals, and tend to attack cities and things, leaving devastation behind.

This is a pretty loose definition, though. So...

King Kong. Huge gorilla and protector of Skull Island. Otherwise, not particularly fantastical.
Is King Kong a kaiju?
Yes
67.2%
No
6.3%
Maybe?
14.1%
No but those big monster things he fights are
12.5%
Poll ended at .

@InvaderXan

(Also, Kong vs. Godzilla was a draw.)

@truculentsheep I'm not sure I've ever actually seen that one TBH

@InvaderXan

In summary, the Failnewt nearly drowns Kong, Kong pwns the Failnewt, the Failnewt goes feral and pwns Kong, then Kong saves the Failnewt's keloid-covered arse from Mecha Failnewt. They then agree to disagree, and the full time score is 2-2.

Also, some boring human subplot shit, which no one cares about, because you don't watch a kaiju film for humans any more than you watch a grumble flick for the dialogue.

@truculentsheep To be fair, done well, the human characters can make a monster movie. Unfortunately, they're just really bad at including human characters in American Godzilla movies.

@InvaderXan

Don't get me started on the fascist cardboard cutouts in Pacific Rim... I was rooting for the kaiju about 5 minutes in.