He who has perfect faith in the Law of Karma, the law of reincarnation Avatara, ancestor worship, Varnashrama Dharma, Vedas and existence of God, he who practises the instructions given in the Vedas with faith and earnestness, he who does Sandhya, Sraaddha, Pitri-Tarpana and the Pancha-Maha-Yajnas, he who follows the Varnashrama Dharmas, he who worships the Avataras and studies the Vedas, is a Hindu."
This is the definition given by some highly cultured men. This is the most appropriate and complete definition in “A Hindu”.