What is the definition or description of: febrile convulsions?

Seizure due to fever: Typically seen in young children, the first symptom is usually the seizure & then noticing the high temperature. It occurs because of a rapid rise of temperature and, what is thought to be, a rapid change in the polarization of nerve cells in the brain. It is important to be seen and evaluated to make sure there is nothing else going on (meningitis,etc).

Febrile convulsion: Febrile convulsions are seizures (fits or convulsions) occurring in children aged 6 months to 5 years, associated with fever, without other underlying cause such as CNS infection or electrolyte imbalance. The mechanisms are unknown. It is uncertain whether the degree of fever or the rate of rise of temperature is a trigger in febrile seizures http://patient.info/doctor/febrile-convulsions