hole science definition

A gap, usually the valence band of an insulator or semiconductor, that would normally be filled with one electron. If an electron accelerated by a voltage moves into a gap, it leaves a gap behind it, and in this way the hole itself appears to move through the substance. Even though holes are in fact the absence of a negatively charged particle (an electron), they can be treated theoretically as positively charged particles, whose motion gives rise to electric current.