I'd say Ra is pretty tanky, considering his high health pool.
I just hate when people yell at a Behemoth to tank. STFU IT'S THE EXACT OPPOSITE.
Or Midas. That's probably a close second.
Tank = Hero you don't want to focus during teamfight, better take him out when the others are dead
Ra = Tank
Oh but yeah, the definition of a "Tank" is highly subjective to anyone, therefore this thread lacks a real topic
can be both :P
Creator of Snakezoor's All Heroes Guides http://www.heroesofnewerth.com/guides.php - Snakezoor
A tank, by technical definition, is a mobile weapons platform that has been heavily armored and optimised to the point of relative indestructability, generally for the purpose of breaking through otherwise inpenetrable defences (see: the periods in the world wars where tanks proved invaluable for such a purpose, and many scenarios in HoN where a defensive deadlock takes place). If this concept was translated to MOBA semantics, heroes that are both difficult to kill while also dealing significant damage and/or having some form of crippling presence fit the bill of "tank." Since most heroes that build survivability either directly or indirectly (read: most carries) fit the description, tank is a debatable term.
I suppose, if we want to directly analyse hero examples, that it might be best to compare Sil and Zeph; both are carries and both build survivability, but it's obvious which one would be called a "tank" by the majority of MOBA communities. Zeph is capable of withstanding defensive countermeasures when initiating (a critical component to RL tanking, particularly for the world wars), and still contributes significant damage and slow in addition to his gusts. Silhouette is likely to excel more at dealing single target damage, and would probably be capable of dealing more consistent DPS than a zephyr; you cannot expect her to stay in the face of an enemy team (assuming it's a competent team) for any period of time, though, without getting ripped a new one and being forced to swap out before doing any significant damage. As such, we can see a zephyr that has effectively crippled an enemy team while continuously remaining at least somewhat relevant, as opposed to a silhouette that carries harder and eventually does much higher dps but is effectively cockblocked out of a fight if she attempts to take the focus away from her teammates, which in itself is a bad thing if she's a primary modicum of damage (a sil cannot, after all, become nearly so tanky as a zeph).
A critical component to the argument, however, is initiators in general. A magmus or behe or tempest or whatever effectively cripples an enemy team in a time period that will suffice for the rest of the team to mop up on stunned, slowed, and damaged targets without having any necessity for the tank described previously. A sil paired with just a pk magmus can easily take out any other two heroes, and probably can remain effective even against a full team of 5 if the sil has progressed far enough. A tank is not necessary at all in such circumstances where any blink initiator can absolutely ruin an enemy team, particularly when the blink initiator has allied heroes with heinous levels of burst dps. The tank can supplant the blink initiator, though, and is probably a better choice against teams capable of withstanding an initial cavalcade of damage after you blink in. Initiators are also not always capable of breaking through defensive deadlocks, as opposed to a tank that can force the enemy to waste resources in some fashion (as in, ignoring something like a zeph if he's barreling in on you with his team is not pragmatic).
A tank really is a legitimate role in HoN, by extensions of its definition and effective validations of the actual entity in various scenarios. What is really arguable is whether a tank is worth picking up as opposed to something else like a mag or temp; whether, that is, if picking a true tank is practical in enough instances within a match to be more useful than an alternative.
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