This document presents an approach for measuring semantic similarity between terms using a semantic network. It discusses limitations of existing knowledge-based and corpus-based approaches. The proposed approach uses a large-scale isA network obtained from web corpus to compute semantic similarity scores between 0 to 1. It introduces a concept clustering algorithm to handle ambiguous terms. Experimental results show clusters of word contexts and similarity scores generated between word pairs using this semantic network approach. The approach provides an efficient way to compute semantic similarity, especially for large datasets.