The Tavern

I already do this but I just wanted to know is stair dancing the one where you use multiple stairs with the intent of not taking a hit when coming up or is it where you abuse the mechanic of enemies following you up stairs to only deal with a small number of enemies at a time (V5 for example).

Some of both. There are too many monsters downstairs to fight head-on, so you go up and down the stairs to render a difficult fight easy. The specific route you take doesn't matter for the definition of the term, although depending on what you're trying to stair-dance one route or another might be better.

What is kitting?

Kiting means hurting something from range and then keeping distance so that you're not exposed to melee attacks. This can be done with a fast species (attack a few times, run away to gain distance, then attack again) or using poison (cast Sting / use poisoned ammo, run away while the victim suffers continuous damage from poison, reapply poison when necessary).

don't forget "stair kiting": when the down-stairs are right next to each other and the up-stairs are about 1 LOS radius apart, so dancing between the staircases lets you kite an enemy back and forth forever. works best against monkeys.

Kiting works vs non-melee monsters too.
1) Monster's Fireball/Bolt of fire etc. is not full range so you can still shoot at the enemy on the edge of view with your arrows/Air strike/Magic Dart whatever
2) Normal speed character can kite Cyclops, they spend more than 1.0 turn to move so you get less damage if you move and shoot with arrows, move and shoot with arrows instead of just standing and shooting. Though usually I don't bother.

There is another way of stairdancing: stairs to Depths often have just a single adjacent tile so you can move upstairs with 8 adjacent monsters to fight them one at a time.

Broadest definition of these and some related tactics would be something like this:

Stair dancing: tactical use of stairs (mostly, but potentially hatches as well) to give player an advantage in fighting
Kiting: maintaining a certain distance against foe(s) while still dealing damage or otherwise seeking to hurt them
Pillar dancing: maintaining a certain distance against foe(s) while player is recovering (HP/MP/status/etc.)
Luring: leading an enemy into an area in order to fight on more favorable terms


Players or devs will sometimes bring these up as issues that lead to repetitive/tedious tactics, but part of the problem is that in some cases being able to do limited versions of the above things is just "good tactical decision-making" and potentially interesting. Unfortunately many of these tactics are abusable due to (e.g.) the fact that many enemies are same speed or slower than player, species with faster than 10 movespeed exist, etc.

So, depending on the context, "stair dancing" can refer to abuse of stairs in the game. (E.g., a GDD thread titled "nerf stair dancing") Or it can refer to less extremely abusive, more "standard" tactics. Where exactly one ends and the other begins is blurry, open to debate, etc.

One thing to watch out when stair dancing: climbing stairs takes a long time in Crawl, and all the monsters get to attack you while you're lumbering up or down a floor.

Stair dancing was nerfed in the last patch though wasn't it?

It was more a chance for consistency|transparency sake.
I don't think this affect significantly the balance in situations where stair dance is a good tactic (which is almost always). I mean probably more delay - more EV is going to be noticeably worse in extreme cases like when you try to stair-dance with an adjacent hydra, but this has never be a good move, so...