overdye means to dye (something already coloured) with another colour. Lexicurio rates it Sui generis — a strength score of 87 out of 100.
Etymology
From over- + dye.
verb
- To dye (something already coloured) with another colour.“To last more than a few days in the sunshine, the crushed logwood needed to be over-dyed on woad- or indigo-coloured fabric.”
- To dye too much.“Near-synonym: overcolor”