What are monsoon rains exactly?

Answer 1

Monsoon rains are the rains carried by a wind called monsoon.
More info on monsoons you can find here:

Answer 2

Monsoon winds are seasonal winds which flow with consistency and regularly for one part of the year and blow from the other direction for the other part of the year.The winds are generated due to differential heating of the land and water by the solar radiation.
For example, the south-west monsoon which blow over India is the result of the differential heating of the Northern Hemisphere(land area) and the Southeren Hemisphere(sea area) during the northern summer.Due to this differential heating,the cooler moist air from the southern hemisphere starts moving towards the hot northern hemisphere.This wind crosses the equator and is deflected by coriolis force and reaches the western coast of Penisular India .There, the wind is met by the western ghats mountain range resulting in heavy rains on the windward side of the mountain.The rains,thus brought by the monsoon winds regularly every year is called monsoon rains.
The sea-breeze and the land breeze which are occuring along the coastal stations is formed in a similar way and can be called mini-monsoons (as it is occuring on a small scale) .

Answer 3

Monsoon rains are wet monsoons. Monsoons are seasonal winds that either bring dry or wet weather.