" aloof! An old expression meaning 'Keep your luff', or sail as close to the wind as possible. Sometimes, in old books of voyages, written as 'ALUFFE'. The expression was most often used when a ship was sailing along a lee shore, the order to 'keep aloof' meaning to keep the ship's head nearer to the wind to prevent her being driven closer to the shore. "

Any etymology experts among us able to tell how this nautical term changed to mean

"distant in sympathy, interest, etc.; reserved and cool !her manner was aloof"