kühlen
to cool
To make something cold or lower its temperature.
Wir sollten die Getränke für die Party im Kühlschrank kühlen.
We should cool the drinks for the party in the refrigerator.

to cool
Loading your saved state.
to cool
To make something cold or lower its temperature.
Wir sollten die Getränke für die Party im Kühlschrank kühlen.
We should cool the drinks for the party in the refrigerator.

The verb "kühlen" (to cool) is derived directly from the adjective "kühl" (cool). It describes the action of making something or oneself cool.
Eine kühle Brise wehte vom Meer herüber.
A cool breeze blew in from the sea.
When a person cools down their own body, the verb is used reflexively: "sich kühlen" (to cool oneself off). The reflexive pronoun (sich, mich, dich, etc.) is necessary here.
Nach dem langen Lauf kühlte ich mich unter der kalten Dusche.
After the long run, I cooled myself off under the cold shower.
The idiom "sein Mütchen an jemandem kühlen" (to take it out on someone) is a fixed unit. It means to vent one's anger on a person. The person who receives the anger always appears with the preposition "an" in the dative.
Er war wütend auf seinen Lehrer und kühlte sein Mütchen an seinem kleinen Bruder.
He was angry with his teacher and took it out on his little brother.
In a medical context, "kühlen" (to cool) is often combined with body parts or injuries. Typical phrases are "den Knöchel kühlen" (to cool the ankle), "eine Schwellung kühlen" (to cool a swelling), or "die Wunde kühlen" (to cool the wound).
Der Arzt sagte, ich solle das Knie regelmäßig kühlen.
The doctor said I should cool my knee regularly.
to omit / leave out
'kühlen' and 'auslassen' are similar here only in a fixed expression: 'sein Mütchen an jemandem kühlen' means roughly to take one's anger out on someone. So both expressions describe someone venting negative feelings on another person, often on someone who is not responsible. The difference is important: in this meaning, 'auslassen' can be used directly with 'Ärger' or 'Frust'. 'kühlen' does not have this meaning on its own, but only in the expression 'sein Mütchen an jemandem kühlen'. Learners might confuse the words if they do not recognize the fixed expression. In everyday language, 'seinen Ärger an jemandem auslassen' is much more direct and easier to understand.

Nach dem Streit kühlte der Chef sein Mütchen an seinem Assistenten.
After the argument, the boss took it out on his assistant.
Bitte lass deinen Ärger nicht an den Kindern aus.
Please don't take your anger out on the children.