relative

https://doi.org/10.1351/goldbook.R05255
Quotient of quantities having the same @K03393@ in different systems.
Notes:
  1. The denominator quantity is often called the reference quantity.
  2. Preferentially the same component is found in the numerator and denominator quantity.
Source:
PAC, 1996, 68, 957. (Glossary of terms in quantities and units in Clinical Chemistry (IUPAC-IFCC Recommendations 1996)) on page 989 [Terms] [Paper]