A social networking system determines the meaning of an anchor term used in a communication received from a communicating user. Candidate nodes are identified in the dictionary based on the anchor term, where each candidate node represents a possible meaning of the anchor term. The context of the anchor term is determined, and a score is determined for each candidate node based on the determined context. A candidate node is selected that most likely represents the meaning of the anchor term based on the determined candidate node scores. The context of the anchor term may be a social context derived from users connected to the communicating user that use the anchor term in communications. A communicating user may be prompted to identify the meaning of the anchor term explicitly based on the use of the term in communications from other users connected to the communicating user.