Turning Points & Changes
* Turn of events: An unexpected or significant change in the course of something.
* Take a turn for the worse: To deteriorate in condition or quality.
* Turn over a new leaf: To make a fresh start, change one's behavior.
* Turn the tide: To change the course of something, usually for the better.
* Turning point: A moment when a significant change occurs.
* In the blink of an eye (or in the turn of a hand): Very quickly.
Movement & Direction
* Turn around: To change direction, to reverse course.
* Turn left/right: To change direction while moving.
* Turn the corner: To reach a point where improvement is likely.
* Turn back: To return to a previous location.
* Turn up: To appear unexpectedly.
* Turn out: To develop in a particular way.
* Turn in: To go to bed.
Actions & Effects
* Turn on/off: To activate or deactivate something.
* Turn down: To refuse an offer.
* Turn up the volume: To increase the sound.
* Turn a blind eye: To ignore something.
* Turn a profit: To make money.
* Turn something into something else: To transform something.
* Turn someone's stomach: To make someone feel sick.
Figurative Language
* Turn the tables: To reverse the situation to one's advantage.
* Turn a deaf ear: To ignore someone.
* Turn a profit: To make money.
* Turn someone's head: To make someone arrogant or vain.
* Turn of phrase: A distinctive way of expressing oneself.
* Turn the clock back: To return to a previous time.
Other Phrases
* In turn: As a consequence.
* Take your turn: To have your opportunity.
* By turns: Alternating.
* Take a turn: To take a walk or drive.
* Take turns: To alternate doing something.
This is not an exhaustive list, but it gives you a good starting point for thinking about how the word "turn" can be used in different contexts.