Lubricating oil base oil, lubricating oil composition containing same, and continuously variable transmission using said lubricating oil composition

A lubricant base oil, comprising:

• a ring-comprising compound comprising:
• (i) a crosslinked bicyclic ring in which two rings are bonded while sharing 3 or more carbon atoms;
• and
• (ii) an acyloxy group or a hydrocarbyloxycarbonyl group each comprising a branched hydrocarbon group with a main chain having 4 or more carbon atoms,
• wherein the ring-comprising compound has formula (1) or (2):
• wherein
• R11 and R21 are independently a crosslinked bicyclic ring in which two rings are bonded while sharing 3 or more carbon atoms,
• A11 and A12 are independently a single bond or a hydrocarbon group,
• R12 and R22 are independently a branched hydrocarbon group with a main chain comprising 4 or more carbon atoms,
• X11 and X21 are independently a hydrocarbon group, and
• p11 and p21 are independently an integer in a range of from 1 to 4.