Use the noun touchstone to describe a basis for comparison. For example, a filmmaker's touchstone might be her all-time favorite movie; she wants her movie to be that good or similar to it in some way.

Pronunciation: /'tʌtʃ'ston/
English description: a basis for comparison; a reference point against which other things can be evaluated
Synonyms: criterion
Chinese Translation: 试金石(shi4 jin1 shi2)
Spanish Translation: la piedra de toque
ORIGIN: Touchstone as it is defined today comes from an actual stone. In the late 15th century, gold and silver was rubbed, or touched against black quartz — the touchstone — to determine the purity of the metals. This was done by looking at the color of the streaks left on the stone. This is why a touchstone, in the figurative sense as it is used today, is a measuring tool.

EXAMPLE SENTENCE:

Projections for 20 scenarios for nine indicators, and touchstone scenarios for one indicator.
Many of today’s feminists see abortion as one of the touchstones of their movement.

*New word description, story and part of "EXAMPLE SENTENCE" are cited in Vocabulary.com