partition

This term is often used as a synonym for distribution and extraction. However, an essential difference exists by definition between distributionconstant or partition ratio and partition constant. The term partition should be, but is not invariably, applied to the distribution of a single definite chemical species between the two phases.
Source:
PAC, 1993, 65, 2373 (Nomenclature for liquid-liquid distribution (solvent extraction) (IUPAC Recommendations 1993)) on page 2378