The phrase "very existence" means the state or fact of being alive or existing. It refers to the actual presence or being of something or someone. Full definition
First and foremost, time was a factor in this game's very existence in the first place. (nintendowire.com)
The device seems to be aimed at not just any old privacy - concerned user, but those whose very existence depends on retaining their privacy and anonymity, for one reason or another. (androidheadlines.com)
With most insurers, a medical exam is essential when purchasing very existence insurance coverages, and especially once the insured party is of retirement age. (m2insurance.com)