This document summarizes Gerard de Melo's presentation on learning multilingual semantics from big data on the web. It discusses how lexical and taxonomic knowledge can be extracted at large scale from online resources like Wiktionary, Wikipedia, and WordNet. Methods are presented for merging structured data like knowledge graphs and integrating taxonomies across languages using techniques like linear program relaxation and belief propagation. The goal is to build large yet reasonably clean multilingual knowledge bases to power applications in areas like semantic search and the digital humanities.