Unloosen-Loosen | Commonly Confused Words

Unloosen

To make something less tight or confined, often referring to making things free or enabling movement.

I need to unloosen the knot in this rope.She tried to unloosen the jammed drawer.Unloosen the gears before starting the machine.

/ˈluːsən/

To make something less tight or more relaxed

Gently loosen the soil around the plant roots.She tried to loosen the lid with a rubber grip pad.He did exercises to loosen his tight muscles.

Unloosen is often considered a redundant or non-standard way to say loosen.
Loosen is the standard term used for making something less tight.
You can think of unloosen as undoing a state of being loosened, even if it's not widely accepted.
They both technically mean to make something less tight, but loosen is more widely understood and correct.
Try to avoid using unloosen as it may cause confusion due to the prefix un- which typically suggests a reversal.