Snyk is short for 'So Now You Know'.
There isn't a simple answer as it depends on who you ask! Depending on who you speak with, it is pronounced in different ways.
Guy, one of the founders, pronounces it the same as "sneak". There are others within the team that pronounce it like "snick" - the noise a lock makes when it is shutting, as it makes you more secure.
We don't really mind whichever way you pronounce it, as long as you are finding and fixing your vulnerabilities!