To understand and share someone's feelings or troubles, showing that you care about what they're going through; this is the British spelling of sympathize.
From Greek 'sympatheia' (fellow-feeling), combining 'syn-' (together) and 'pathos' (feeling/suffering). Entered English in the 1600s.
Sympathy and empathy get confused, but sympathise literally means 'to feel with' someone—it's about shared emotion, while empathy is about understanding their perspective, even if you don't feel it yourself.
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