stem the tide - Phrases/Idioms
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Stop the course of a trend or tendency, as in It is not easy to stem the tide of public opinion. This idiom uses stem in the sense of “stop” or “restrain.” [Mid-1800s]