Durgshah is term of brahmgyan used in Dasam Granth, a Masculine word, used for intuitive and discerning mind which fight with deamns of inside and outside. Durgshah have weapons of Wisdom, which is use according to need in battle of discussion. Durga is feminine word where durgshah is masculine word. Durgshah mans Gurmukh.
DurgShah is mixture of two words Durg + Shah, Durg means Fort and Shah means King i.e King of Fort is called Durgshah.
In Gurmukh Interpretation, Gurmat is Godess(ਮਤੀ ਦੇਵੀ ਦੇਵਰ ਜੇਸਟ). The Mind which turned into intuitive and discerning mind is called Chandi.
ਦਾਸ ਕਮੀਰ ਚੜਹਹਿਓ ਗੜਹਹ ਊਪਰਿ ਰਾਜ ਲੀਓ ਅਬਿਨਾਸੀ ॥੬॥੯॥੧੭॥
When a person break all his manmatt and his mind convert into Intuitive and discerning mind, (ਚੜਹਹਿਓ ਗੜਹਹ ਊਪਰਿ = Durg), and he become king of world (ਰਾਜ ਲੀਓ ਅਬਿਨਾਸੀ = Shah ), Gurmukhs interpret that whoseoever have this sitiation is called DURGSHAH. Durgshah is for person and Durga is his Matt. Chandi, Durga, Shiva are name of Matt of Durgshah.
In Hindu's Interpretation, it is some goddess, having some form, living in himalayas and is wife of Mahadev Shivji, which is totally opposite to defination of Chandi/Durgshah by Guru Gobind Singh.