Definition:
"Ruining" is the present participle form of the verb "ruin." It means to cause something to be destroyed, damaged, or made worse. When something is ruined, it can no longer be used or enjoyed as it was before.
Physical Destruction: When something is broken or damaged beyond repair.
Figurative Destruction: When something is harmed in a less tangible way, such as a reputation or a feeling.
"To ruin someone's day": This means to do something that makes someone unhappy or spoils their plans.
"To ruin the surprise": This means to give away information that takes away the excitement of a surprise.