Words created to fill a void in the language, usually spontaneously created during conversation. Terms created through evolutionary vogabulary are usually a combination of two or more words, that when woven together more perfectly express an idea.
Annie, Felisa, and Peter were discussing the night that Charlotte got petrifurious at Peter for jumping out of the bushes along the dark walkway next to their house. She cried the whole time she whaled on him, and he was laughing so hard he couldn't get her to stop until he was pissterical. Annie realized that in their rush to define the event, they had discovered evolutionary vogabulary.