"Stellar reviews" means receiving extremely positive and excellent feedback or comments about something, like a product, service, or performance. Full definition
These 125 organizations get stellar reviews from their employees. (bostonglobe.com)
Similarly to the above entry, the game received stellar reviews from critics but yet it is the multiplayer where the problems happened to surface. (relevant-gaming.com)
All pointless arguments, both games are receiving stellar reviews from all sites only because both are stellar games. (n4g.com)