This is the 2662nd most frequent German word.
elektrische
"Elektrische" means "electric" in English.
Here, 'elektrische' acts as an adjective describing the type of toothbrush — electric.
Die elektrische Zahnbürste macht das Zähneputzen einfacher.
The electric toothbrush makes brushing teeth easier.
In this sentence, 'elektrische' describes the type of devices, indicating that they operate using electricity.
Elektrische Geräte sollten immer vorsichtig verwendet werden.
Electrical devices should always be used carefully.
Here, 'elektrischen' is used in its declined form to conform to the feminine noun 'Heizung' while describing its type — electric.