Squeaky describes a high-pitched sound that reminds you of a mouse's cry or a rusty door hinge. A squeaky wheel on a shopping cart makes that annoying eee-eee-eee noise as it rolls. New sneakers on a gym floor often make squeaky sounds. When someone has a squeaky voice, it sounds thin and high, sometimes cracking or wavering.

The word comes from squeak, which is both the sound itself and the verb for making it. You might hear a mouse squeak in the walls, or notice your bed squeaking when you roll over at night. Things squeak when parts rub together without enough oil, when air escapes through a small opening, or when something is new and stiff.

People sometimes use squeaky to describe someone who's overly proper or rule-following, calling them squeaky clean. This phrase suggests someone is so perfectly behaved that they almost seem too good to be true, like they've been scrubbed free of any dirt or mischief. A squeaky clean reputation means others see you as honest and trustworthy, though sometimes people use the phrase with a hint of suspicion, wondering if anyone can really be that perfect.