olemus
Wiktionary:
2. a measurement one can compare to
8. a relation between objects in which one object designates, or acts as a means by which to connect to or link to, another object

näiteid
reference configuration -- etalonkonfiguratsioon
reference fuel -- etalonkütus
reference implementation -- etalonteostus
reference lamp -- etalonlamp
reference material -- etalonaine; etalonmaterjal
reference model -- etalonmudel
reference oil -- etalonõli
reference power -- etalonvõimsus
reference standard -- võrdlusetalon; tugietalon