False Colour
Coloured artefacts appearing on fine detail, caused by the colour filter array sampling different colours at different positions.
In depth
Because red, green and blue are recorded at physically separate photosites, a fine edge can land on one colour's samples but not another's, producing a coloured fringe that has no counterpart in the subject. It is a companion artefact to moiré and is usually removed in raw processing by a dedicated colour-smoothing control.
Examples in practice
A distant white radio mast against blue sky shows alternating red and cyan speckles along its length.