Andronicus of Cyrrhus or Andronicus Cyrrhestes (Greek: Ἀνδρόνικος Κυρρήστου, Andrónikos Kyrrhēstou), son of Hermias, was a Greek astronomer best known as the architect of the horologion at Athens called the Tower of the Winds. Andronicus also built a multifaced sundial in the sanctuary of Poseidon on the Greek island of Tinos. He flourished about 100 BC.
He built a horologion at Athens, the so-called Tower of the Winds, a considerable portion of which still exists. It is octagonal, with figures carved on each side, representing the eight principal winds. In antiquity a bronze figure of Triton on the summit, with a rod in his hand, turned round by the wind, pointed to the quarter from which it blew. From this model is derived the custom of placing weather cocks on steeples.