To soothsaid means to say what will happen in the future, like a magic person in a story.
Soothsaid can make people think of old stories, magic, or mystery.
Examples:
The old woman soothsaid that the king would lose his crown.
The wizard soothsaid that a great hero would come to save the kingdom.
She soothsaid the weather would be bad, and it was!
The cat soothsaid that it would rain fish, but it didn't.
The soothsaid words came true, just like in the stories.
The soothsaid prophecy changed the kingdom forever.