Actor Surya used that word in Soorarai Pottru, following actor Vijay in Master and G V too uttered the word '**tha' in his upcoming film while expressing his anger. I don't know what that means, but it's definitely an word. Heroes are better off avoiding this as it may affect the growing generation.
I have heard some people speak this word casually, but since words like this come up in the films, it too will definitely affect the younger generation when great actors speak that word. I wish they do not create an "F word" culture in Tamil!