1. lacking enthusiasm, energy, or conviction; done with little effort or interest
He made a half-hearted attempt to apologize.
Ele fez uma tentativa sem entusiasmo de se desculpar.
2. not wholehearted; lacking sincerity or commitment
Her half-hearted smile showed she was not happy about the decision.
Seu sorriso sem convicção mostrava que ela não estava feliz com a decisão.