Noun
GCSI (plural GCSIs)
post-nominal letters for a person who has been awarded the position of Grand Commander of the Order of the Star of India.
The first woman to be granted a knighthood in modern Britain seems to have been H.H. Nawab Sikandar Begum Sahiba, Nawab Begum of Bhopal, who became a Knight Grand Commander of the Order of the Star of India (GCSI) in 1861, at the foundation of the order. Source: Internet