lash against
1. To beat, flail, or strike violently or wildly against someone or something. The waves lashed against the side of our boat during the storm.
2. To swing, whip, or flail something against someone or something. In this usage a noun or pronoun is used between "lash" and "against." The wind kept lashing the branches of the tree against my window.
lash against something
[for something, such as wind or water] to beat or whip heavily against something. The angry waves lashed against the hull of the boat, frightening the people huddled inside. The wind lashed against the house and kept us awake all night.