Plain English Meaning
How much electricity all the aircraft's switched-on equipment is using right now, added together.
Full Definition
The total electrical current, measured in amperes (amps), being drawn from an aircraft's electrical system by all powered equipment in use at a given moment.
Context Anchor
Seen in electrical system malfunction procedures, especially when the pilot may need to turn off nonessential equipment to save battery power.
Derivation
Amperage' comes from 'ampere,' the unit of electric current named after French physicist André-Marie Ampère. 'Load' here means the demand placed on a — the same sense as a workload. Together: the amount of current demand on the electrical system.