1. A computer-implemented method for determining a topic of a communication term in a social networking system, the method comprising: receiving a communication from a communicating user; identifying an anchor term in the communication; identifying a set of candidate nodes from a dictionary that comprises a set of dictionary nodes, each dictionary node representing a topic, wherein the identified candidate nodes are selected from the dictionary nodes that represent topics related to the anchor term; determining a score for each of one or more of the candidate nodes based at least in part on one or more dictionary nodes associated with communications from other users who are connected to the communicating user in the social networking system, the communications also containing the anchor term; presenting one or more of the candidate nodes to the communicating user based on the determined scores; and prompting the communicating user to select one of the presented candidate nodes.