verb (used with object)
to diminish or end the congestion of.
Origin of decongest
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
To relieve congestion, such as of the sinuses.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.