peak

Also contains definition of: unresolved peak in chromatography

in chromatography
The portion of a differential chromatogram recording the detector response when a single component is eluted from the column. If separation is incomplete, two or more components may be eluted as one unresolved peak.
Source:
PAC, 1993, 65, 819 (Nomenclature for chromatography (IUPAC Recommendations 1993)) on page 835
Orange Book, p. 96
Orange Book, p. 101