loose / to loosen / to relax / floss (dry, fluffy food product made from shredded, seasoned meat or fish, used as a topping or filling)
松
=
公
+
木
:
Mnemonic symbol: 松鼠, a squirrel.
The squirrel (松) almost got a heart attack when it drove its bus (公) off of one of the stones in front of the engine ((e)ng1), but as it realizes it got stuck in the Susan Saint Bernard's (su) web which spans a Christmas tree (木) and one of the engine's boulders the squirrel (松) relaxes (放松).