A monsoon is traditionally a seasonal reversing wind accompanied by corresponding changes in precipitation but is now used to describe seasonal changes in atmospheric circulation and precipitation associated with annual latitudinal oscillation of the Intertropical Convergence Zone (ITCZ) between its limits to the north and south of the equator. Usually, the term monsoon is used to refer to the rainy phase of a seasonally changing pattern, although technically there is also a dry phase. The term is also sometimes used to describe locally heavy but short-term rains.

भारतम् ऋतुनां देशोऽस्ति । अत्र षड् ऋतवो भवन्ति - ग्रीष्मः, वर्षा, शरद्, हेमन्तः, शिशिरः वसन्तश्च । वर्षा-ऋतुः ग्रीष्मात् अनन्तरम् आगच्छति । एतस्य कालः जुलाई मासतः सितम्बरमासपर्यन्तं भवति । श्रावण - भाद्रौ च अस्य भारतीयौ मासौ स्तः ।