Definition of rotten-hearted in US English:

rotten-hearted

adjective

  • 1Of a thoroughly corrupt nature or character; wicked through and through; extremely unkind or unpleasant.

  • 2Of a tree, root, etc.: that has rotten heartwood.

Origin

Late Middle English; earliest use found in Geoffrey Chaucer (c1340–1400), poet and administrator. From rotten + hearted.

Pronunciation

rotten-hearted

/ˌrɒtnˈhɑːtɪd/