Meaning
To be heartbroken / To be jealous
Example
Ele está com dor de cotovelo depois que foi abandonado pela mulher.
He's heartbroken after being dumped by his wife.
Origin
The expression estar com dor de cotovelo (literally "to have elbow ache") is tied to the verb acotovelar and the gesture of nudging someone with the elbow — a sign once used to point out and quietly mock or criticize, often out of envy. Someone forever delivering such jealous jabs would, naturally, end up with a sore elbow, so the aching elbow came to stand for envy and, by extension, the bitter sting of jealousy and lovesickness.
Sources: Ciberdúvidas da Língua Portuguesa, Só Português.
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