Ampacity
/ˌæm.pəˈsɪt.i/noun
The maximum amount of electric current a conductor can carry safely.
Did you know?Ampacity is a 20th-century engineering coinage built from ampere + capacity, so its “mystery” is not occult history but the practical magic of naming a wire’s safe current limit.
Etymological Timeline
18th Century
French
ampère
“A unit name derived from the surname of André-Marie Ampère, the physicist whose work helped define electromagnetism.”
19th Century
English
ampere
“The unit of electric current named after Ampère.”
14th Century
Latin
capacitas
“Capacity, receptiveness, or room for holding.”
19th-20th Century
English
ampacity
“A technical term formed from ampere + capacity to mean the current-carrying capacity of a conductor.”