A company's "burn rate" refers to how quickly it is burning through cash.
A company’s “burn rate” refers to how quickly it is burning through cash. This isn’t often an issue for large, established companies, but with small and quickly growing ones, a glance at the burn rate can be valuable. Look at free cash flow, which is income from operations, less capital expenditures.
For example, take a company that reported negative $20 million in free cash flow in its most recent quarterly report — as its cash balance fell to $80 million from $100 million. It’s not unusual for firms to lose money in their early years, but it’s also what puts many of them out of business. To stay alive, a company burning through money will have to reduce spending (possibly resulting in slower growth) or find more money (perhaps issuing additional stock, diluting value for existing shareholders).
— The Motley Fool