A tanking character that is acting like, a little sissy and entering combat last.
A caster or other low-hp character that is acting like a tank for no good reason and overall fucking up everybody's game.
"Why is Rammus backing out?!?!"
"F*ck.... we got a french tank"
"Ok, once they are in range Alistar is gonna stun'em and then... Wait, wait Ryze wtf u doing man?!?!"
"He frenched tanked them...."
Used extensively in both World Wars.
English Sergeant: It's the French Tank sir - it has finally been perfected after nearly 100 years of development.
English General: Well I never - what will those onion-eating cunts think of next?