"base level" refers to the starting or lowest point of something. It is the foundation or the fundamental level from which things begin or are measured. Full definition
Loss of use coverage starts at $ 3,000, though $ 4,500 is a more common base level of coverage. (effectivecoverage.com)
But there's also fresh instrument graphics, a new centre console, new climate controls, a new flat - bottom three - spoke steering wheel and cruise control at base level. (motoring.com.au)
By creating facilities, players will be able to level up their bases, with story progression tied to specific base levels in each chapter. (wccftech.com)