IPA: /rɪˈvɜrslɪ/
KK: /rɪˈvɜrsli/
In a way that is opposite to the usual or expected direction or order.
The two cars moved reversely to avoid the traffic jam.
Reversely → It is formed from "re-" (meaning again or back) and "versus" (meaning turned). The word "reversely" means in a manner that is turned back or in the opposite direction.
Think of something being 'turned back' ('versus') again ('re-') — that's why reversely means to do something in the opposite way.