an expression for the antiknock rating of a motor gasoline as a guide to how vehicles will operate under mild conditions associated with low engine speeds

standardne mõõtesuurus, mille abil tehakse kindlaks mootori talitluse või bensiini plahvatuskindlus, s.o isesüttimise vastu seismise võime, standard measure of the performance of an engine or aviation fuel, standard measure of a fuel's ability to withstand compression in an internal combustion engine without undergoing pre-ignition