Straight from a Google search “define: burn rate” — ‘the rate at which an enterprise spends money, esp. venture capital, in excess of income.’ This really isn’t a term I have heard of before for that context, and I am here to tell you it’s something you’ll want to be mindful of.
Stay lean with your saleries. Any big strain on your startup’s budget will keep investors who would be otherwise interested from putting in any capital. I have for that reason myself elected to take a paycut on my salary to run at the bear minimums to get our burn rate down as low as possible. It’s painful but in the end the right choice to make.