In such models, the meaning of a word is defined by its relationship to representations of the language users' environment.
for a robot operating in a laboratory setting, words for colors and shapes may be grounded in the outputs of its computer vision system (Roy & Pentland, 2002); while for a simulated agent operating in a virtual world, words for actions and events may be mapped to representations of the agent's plans or goals (Fleischman & Roy, 2005).