1. Relating to or arising from an odd, unusual, or distinctive individual characteristic or habit
His idiosyncratic way of dressing made him stand out in the crowd.
Sua forma idiossincrática de se vestir o fazia se destacar na multidão.
2. Peculiar to a particular individual; unique in constitution or temperament
Each writer has their own idiosyncratic style.
Cada escritor tem seu próprio estilo idiossincrático.
3. In medical contexts, relating to an unusual or unexpected reaction to a substance
She had an idiosyncratic reaction to the medication.
Ela teve uma reação idiossincrática à medicação.