tr.v. up·built (-bĭlt′), up·build·ing, up·builds
To build up; increase or enlarge: sand dunes that were upbuilt by the wind.
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.
vb, -builds, -building or -built
(tr) to build up; enlarge, increase, etc
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
Past participle: upbuilt
Collins English Verb Tables © HarperCollins Publishers 2011