陪都

péidū
  1. provisional capital of a country (e.g. in time of war)
  2. secondary capital
  3. alternative capital

CEDICT

  1. (historical) secondary capital of a country
  2. secondary capital of a country

Wiktionary

首都以外，另建的第二国都。如我国抗战前定西安为陪都，抗战期中定重庆为陪都，抗战后又定北平为陪都。

重編國語辭典

一个政权在首都之外另外设立的都城

維基詞典

Entry Composition

1 陪 péi
  1. to accompany
  2. to keep sb company
  3. to assist
  4. old variant of 赔 péi
2 都 dū
  1. capital city
  2. metropolis