This is the 5291st most frequent Russian word.
окунаться
To plunge or immerse oneself (into water or an activity).
In this sentence, "окунаться" means to physically immerse oneself, typically into a liquid.
Каждое утро он окунается в ледяную воду.
Every morning, he immerses himself in icy water.
Here, "окунаться" is used metaphorically to describe deeply engaging oneself in an activity.
Мы любим окунаться в изучение новых языков.
We love to immerse ourselves in studying new languages.
This usage of "окунаться" illustrates dedicating oneself to an enjoyable pastime or activity.