Small seizures that are part of a larger seizure disorder.
Subseizures are a medical term and are usually a sign of a serious health condition.
Examples:
He has subseizures almost every day.
The doctor is studying her subseizures.
Subseizures can be scary for the person having them.
The cat's subseizures make her owner worried.
The subseizures happen so often, it's like a never-ending storm in his head.
The subseizures are like tiny storms in his brain.