neu·ro·fi·bro·ma·to·sis (no?or??-f??br?-m?-t??s?s, nyo?or?-)n. Abbr. NF Any of several genetic diseases characterized by the development of benign tumors of the nerves and, in the most common form, associated with abnormal skin pigmentation and bone deformities.American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.neurofibromatosis (?nj??r???fa?br?m??t??s?s) n (Medicine) a condition characterized by the formation of benign tumours on the fibrous coverings of the peripheral nerves and the development of areas of café-au-lait spotsCollins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014neu?ro?fi?bro?ma?to?sis (?n??r o? fa??bro? m??to? s?s, ?ny??r-) n. a genetic disorder characterized by brown patches on the skin, neurofibromas of the skin and internal organs, and in some cases skeletal deformity. Random House Kernerman Webster’s College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.