It means ankle holder. He came out of the womb holding Esau's ankle to try and get the blessing of the first born.
Yaakov is hebrew for the word Jacob. This name goes back to biblical times to mean exactly "ankle holder". This means ankle holder because when Jacob was birthed by Rebecca, he was born holding his brother, Esau's ankle. He did this because he wanted the blessing of the first born, which means he gets a double share of everything his parents owned. Nevertheless, he was the second born twin of Rebecca and Isaac, but later in life, he tricked his very sick and blind father into thinking that he was Esau and got the double share.