Slang One who shows difficulty in grasping reality or in responding appropriately to it; a spacy person: "the screwups and the space cadets—in other words, the fringe element” ( Linda Ellerbee). (noun)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.