Architecture Joined to or by a wall, especially by sharing a wall with another building; not freestanding: a block of attached houses.
Biology Living in a permanently fixed state in the adult stage, as the barnacle.
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.