It is simply called a 'nervous laugh' and some people will laugh if they are shy or frightened and it is not meant to be disrespectful, but just the way their body and mind react to being frightened.
I don't know, what do people in Madagascar call Santa Clause?
Santa Claus
People in Ireland call him Santy, Santa and Santa Claus. Santa Claus comes from Saint Nicholas and can then be shortened to Santa Claus or just Santa or Santy. So people in Ireland use those names, like people in many countries do.
聖誕老人 that is how you call santa
They call him Santa Claus. Exactly the same name as you call him.
People in Antactica all came there from other countries, and they would call Santa whatever they call him in their native languages.
We canadians call him Santa Claus, also. Don't worry about it.
They call him Santakukoru.
People in England often call him Father Christmas, but some of them call him Santa Claus as well.
Some people in Britain call him Santa Claus, but others call him Father Christmas, and other names.
People in Pakistan call Santa Claus Baba Christmas