An O-type star in the Delta Quadrant
An O-type star was a classification of star.
In 2256, the USS Discovery jumped into the vicinity of an O-type star using the spore drive instead of its intended destination Corvan II. (DIS: "The Butcher's Knife Cares Not for the Lamb's Cry")
O-type stars usually appear as blue-white. The visual appearance of the star in "The Butcher's Knife Cares Not for the Lamb's Cry" is more consistent with a G-type star or a red dwarf.
The Idran system was a trinary star system consisting of a central supergiant star (FGC-1215) and twin O-type companions. (DS9: "Emissary")
A display showing an O-type star
In 2375, the corona of an O-type star in the Delta Quadrant served to contain the explosion of a Malon export vessel that otherwise would have destroyed everything within three light years. The USS Voyager directed the vessel into the star with a series of tractor pulses, once it seemed that its away team would not be able to avert the explosion. (VOY: "Juggernaut")