What does "Norm" term mean? In this paper (page 1 abstract) which considers regularization technique, the author used the word "norm" - what does it stand for?
Is it related to Batch Normalization / L1 or L2 Normalization? 


  "We stabilize the activations of Recurrent Neural Networks (RNNs) by penalizing
  the squared distance between successive hidden states’ norms"


Googling "what is a norm Neural Net" doesn't provide any links
A norm is a concept in linear algebra which assigns a size to a vector. Many different norms exist you can read up on their many uses here. 

In this paper, they are training a recurrent neural network. These are used for time series data. The assumption is a hidden state should be similar for successive time inputs $t$ and $t-1$. Thus, the author proposes an additional constraint based on the relative size of the successive hidden state vectors as

$||h_{t}||_2 - ||h_{t-1}||_2$.

The more different the norm of these successive states, the greater the cost will be.