in chromatography
asymmetry of a peak such that, relative to the baseline, the front is less steep than the rear. In paper chromatography and thin-layer chromatography, it refers to the distortion of a spot showing a diffuse region in front of the spot in the direction of flow.
Orange Book, 2nd ed., p. 96 (
PAC, 1993, 65, 819. 'Nomenclature for chromatography (IUPAC Recommendations 1993)' on page 837 (