Artículo en inglés del medio especializado Search Engine Watch que nos introduce y explica la búsqueda semántica (semantic search):

SEW… When people speak to each other, they understand more than just words. They understand the context, non-verbal cues (facial expressions, nuances of the voice, etc.) and so much more … “Semantics” refers to the concepts or ideas conveyed by words, and semantic analysis is making any topic (or search query) easy for a machine to understand.