This is the 3022nd most frequent French word.
lâcher
To release, let go, or drop.
Here, 'lâcher' is used in the idiomatic phrase 'lâcher prise', which means to let go of concerns or tensions.
Il faut lâcher prise et ne pas trop s'inquiéter.
One must let go and not worry too much.
In this sentence, 'lâcher' is used in the sense of physically releasing or letting go of something.
Le prisonnier a réussi à lâcher sa corde et à s'échapper.
The prisoner managed to release his rope and escape.
Here, 'lâcher' is used figuratively, meaning to give up or abandon an undertaking or effort.