An exaggeration of 'cankle'. Whereas 'cankle' is a contraction of 'calf-ankle', 'thankle' is 'thigh-ankle'. Indicates that there isn't just no discernable ankle, but no knee either.
Speaker 1. Sally has such cankles.
Speaker 2. No, they're not just cankles, they're THANKLES!
More literal definition: I have no thanks for you because you aren't doing what I want or did something I didn't want.
Example 1:
*toothless, the dragon, flies wildly, terrifying the girl Hiccup's with*
"Thanks for nothing you useless reptile" (How to Train Your Dragon)
Example 2:
"You were supposed to bring hotdog buns! Thanks for nothing."
Thanks Captain obvious is the appropriate response to someone who says something blatantly obvious. This can be said kindly and in jest to one’s friends or spitefully to the jerk that’s been irritating you.
Me: Did you hear in the news about the girl who jumped off of a bridge after leaving a note to her family?
BFF: She must have been suicidal
Me: Thanks captain obvious!