This is the 14395th most frequent Russian word.
отпустить
"To let go" or "to release."
Here, 'отпустить' is used literally to mean releasing a physical object held by hand.
Я отпустил веревку, и воздушный шар улетел.
I let go of the rope, and the balloon flew away.
In this example, 'отпустить' is used abstractly to mean freeing oneself from lingering thoughts or emotions about the past.
Ради достижения спокойствия, я решил отпустить прошлое.
For the sake of achieving peace, I decided to let go of the past.
In this sentence, 'отпустить' is used figuratively to mean letting someone go emotionally or in relational terms.