electoral quota; number of seats needed to win
Technical term used in proportional representation systems; refers to the minimum number of votes or seats required for a candidate or party to secure a seat.
In a proportional representation system, candidates who exceed the electoral quota win seats.
Compound of 当選 (election, winning) + 基数 (base number, cardinal number). The exact historical derivation is uncertain; the term is conventionally associated with electoral systems.