tel·co (t?l?k??)n. pl. tel·cos A telephone company.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.telco (?t?l?k??) npl telcos (Telecommunications) a telecommunications company[C20: from tel(ecommunications) + co(mpany)]Collins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014tel?co (?t?l?ko?) n., pl. -cos. a telephone company. [1975?80] Random House Kernerman Webster’s College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.telcoAn abbreviation for ?telecommunications company.?Dictionary of Unfamiliar Words by Diagram Group Copyright © 2008 by Diagram Visual Information Limited