transfer

Movement of a component within a system or across its boundary. It may be expressed using different kinds of quantities, e.g rates of change $d Q d t$ or $Δ Q Δ t$ . Examples are: mass rate, $d m B d t$ or $Δ m B Δ t$ ; substance rate, $d n B d t$ or $Δ n B Δ t$ .

Source:

PAC, 1992, 64, 1569 (Quantities and units for metabolic processes as a function of time (IUPAC Recommendations 1992)) on page 1573