We are building a site like Fiverr that accepts only advertising "gigs".
We need to use different terminology so it won't be considered like a Fiverr site.
That is contradiction and does not follow. You went out of your way to build a Fiverr knockoff you don't want to seem like a fiverr knockoff, when everyone is going to spend like five seconds and realize "Oh, a fiverr knockoff." But for the small self-delusion of renaming gigs.
That's fooling nobody ...excepting perhaps yourself.