means a shade or trace of color, especially a faint or delicate variation laid over something to alter its hue.

from From Latin 'tinctus,' the past participle of 'tingere,' to dye or moisten with color — the same root that gives us 'tinge' and 'tincture.' The English word was originally 'tint' as a variant of 'tinct,' likely reshaped under influence of Italian 'tinta' (paint, color) used by artists. So at heart it's a dyer's word, the act of dipping something to take on color.