dilute solution

Solution in which the sum of amount fractions of all the solutes is small compared to 1.
PAC, 1994, 66, 533. (Standard quantities in chemical thermodynamics. Fugacities, activities and equilibrium constants for pure and mixed phases (IUPAC Recommendations 1994)) on page 535 [Terms] [Paper]
See also:
Purple Book, 1st ed., p. 57 [Terms] [Book]