Greasy means covered with or containing grease or oil. When you finish eating french fries, your fingers feel slippery and shiny: that's greasy. A mechanic's hands get greasy from working on car engines. Pizza often leaves greasy spots on the cardboard box from all the melted cheese and oil.

The word describes that slick, oily feeling or appearance. Hair becomes greasy when it hasn't been washed and natural oils build up. A greasy stovetop needs scrubbing after cooking bacon. Kitchen towels get greasy from wiping up cooking oil.

People also use “greasy” to describe food that has too much oil or fat. A greasy burger might taste rich but leave you feeling a bit heavy afterward. Some people love greasy food like fried chicken, while others prefer lighter meals.

The word can also describe something unpleasantly slippery or slimy, like a greasy floor that's dangerous to walk on. In older slang, calling someone a “greasy character” meant they seemed sneaky or untrustworthy, like they might slip away from responsibility. That usage is less common today, but you might encounter it in older books.