[dahy-ahr-kee] 
| government in which power is vested in two rulers or authorities. |
| di·ar·chy also dy·ar·chy (dī'är'kē) n. pl. di·ar·chies also dy·ar·chies Government by two joint rulers. |
diarchy
system of double government introduced by the Government of India Act (1919) for the provinces of British India. It marked the first introduction of the democratic principle into the executive branch of the British administration of India. Though much-criticized, it signified a breakthrough in British Indian government and was the forerunner of India's full provincial autonomy (1935) and independence (1947). Dyarchy was introduced as a constitutional reform by E.S. Montagu (secretary of state for India, 1917-22) and Lord Chelmsford (viceroy of India, 1916-21).
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