From mesos (middle) and hēmera (day). Literally 'the middle of the day' — noon. Also used directionally to mean south (since the sun is in the south at midday in the Northern Hemisphere).
In Acts 8:26, an angel directed Philip to go south toward the road from Jerusalem to Gaza, where he encountered the Ethiopian eunuch — one of the most significant conversion narratives in Acts. The word's dual meaning (noon/south) connects to the idea of divine appointments at specific times and places. God orchestrates encounters for the advancement of His kingdom.