1. To eject, erupt, or discharge in a great, spewing rush. Water vomited forth from the spot where the iceberg had struck the hull of the ship. The crowd grew angrier and angrier as the speaker's hateful rhetoric continued vomiting forth.

2. To eject, erupt, or discharge something out in a great, spewing rush. In this usage, a noun or pronoun can be used between "vomit" and "forth." As the ground rumbled ominously, it vomited forth a huge jet of pitch-black crude oil into the air. When I get nervous, I can't help but vomit forth any thought going through my head. I had to pull on the blockage with my hands before the pipe finally vomited it forth.