An interesting symbol that is usually not mentioned is the dance, the Tarantella, that Nora practices for Torvald.
During this dance, Nora is full of excitement, nervous energy and agitation, so she dances wildly and Torvald is displeased with her. Symbolically, the dance, can be seen as Nora's attempt at a full and satisfying life, and Torvald, obviously, does not approve. Nora could never have a more satisfying life with her husband, he does not approve.
He refers to Nora with cute little animal names, like a pet.
"Come, come, my little skylark must not droop her wings. What is this! Is my little squirrel out of temper? (Taking out his purse.) Nora, what do you think I have got here"? Act I
"It's a sweet little bird, but it gets through a terrible amount of money. You wouldn't believe how much it costs a man when he's got a little song-bird like you!" Act I
She is treated like a doll, who must look pretty, and be put on a shelf to be controlled. Nora is not a real person to her husband, in his mind, she can never handle responsibility outside the house. Therefore, when Torvald finds out about Nora's deception it is such a betrayal, a scandal for him.
An obvious symbol is Nora herself. She is the "doll" of the house, pretending to be the perfect wife that her husband wants, but dying inside. Torvald also treats her as if she were a doll. He treats her with kid gloves and as if she were a toy instead of a human being. The things she hides from her husband represent how oppressed she is. Also, Nora represents women of the nineteenth century in Europe (their plight). This time period was marked by males being judged by their work success and women being socially oppressed and relegated to domestic duties.
thanks everyone :)
THE SYMBOLISM OF NORA BEEN A DOLL
Although there are many symbols in A Doll's House, an important symbol is the Christmas tree. The Christmas tree represents Nora; it is something nice to look at. Both the tree and Nora are used to dress up or decorate and for people to admire. Throughout the play it becomes obvious that the tree and Nora are one in the same. AS the tree becomes disheveled and messy so does Nora. Also like the tree, Nora is not to be revealed in her party dress until she looks completely perfect.
Adding to what pmiranda2857 said, the tarantella is quite a wild dance and could perhaps indicate Nora's inner struggle. The dance is a chance for her to break free and prove herself indirectly.
Maybe a question for yourself, looking at kwoo1213's answer, do you think that the author shows signs of feminism?