This is built around hypernym/hyponym hierarchy. Here are some samples to get what this is about.
Cepheid (not RR Lyrae) variable star is a kind of pulsating (not cataclysmic) variable star is a kind of intrinsic (not extrinsic) variable star is a kind of variable star is a kind of star.
Red (not O-type) giant star is a kind of giant (not supergiant) star is a kind of evolved (not main sequence) star is a kind of star.
Cepheid (not RR Lyrae) variable star is a kind of pulsating (not cataclysmic) variable star is a kind of intrinsic (not extrinsic) variable star is a kind of variable star is a kind of star.
Red (not O-type) giant star is a kind of giant (not supergiant) star is a kind of evolved (not main sequence) star is a kind of star.