A sudden, quick movement to one side is a dodge. When you make that movement, you are dodging. One can dodge an object thrown at him or dodge a question he doesn't want to answer.
Ex: The robbery suspect tried to dodge questions the police asked about his movements of the previous evening, but they eventually got the truth out of him.
A dodge can also be a trick. So a dodger is someone who tries not to get caught doing something bad or illegal.
Ex: Some young people take part in a scam called "Dine and Dash". They order and eat a meal in a restaurant and run out before paying. They are all dodgers trying not to pay the bill for the food.
When you hold back, you prevent something from progressing or going any further. Holding back can also mean not doing something as well as you are able to.
Ex: My father holds back when he plays tennis with me. If he used all of his strength, I wouldn't be able to return his serve.
Biting your tongue is an expression that means to hold back something you want to say but probably shouldn't.
Ex: Scott bit his tongue to hold back the comments he wanted to make about Mike's performance in the play. He knew that Mike would be crushed by his criticism.