scum

"During smelting, scum rises to the surface and is then removed by the smelter."

"These organisms form scum in large quantities."

"After years of use, a thick layer of scum had formed on the surface of the septic tank. "

"The biology teacher showed the class a sample of sperm, also called scum. "

"People who sell used-up pens are scum, just total low-lives."

"The chef meticulously scummed the hot broth, removing the floating layer of impurities. "

"The cleaning crew meticulously scums the rain-water runoff from the school's rooftop to prevent clogs. "

"The old water bottle quickly scummed over after sitting in the sun all day. "

"The farmer will scum the pond to remove the algae. "

"The dirty dishes, left unwashed for days, scummed the sink. "

"Context: Imagine someone is playing a challenging video game.

Sentence: "To beat the boss, I had to scum by saving before each attempt and reloading when I failed." "