Ghajnsielem means Salem’s spring (Salem is an extinct Arabic name). The spring is situated at the mouth of Wied Simirat, the valley that now ends in Pjazza tad-Dehra in the very centre of the village.
Ghajnsielem's new parish church is built in gothic style by architect Ugo Mallia. Its foundation stone was laid on 14 September 1924. It was blessed on 27 August 1978 and consecrated on 18 August 1989. The reasons for the delay in completing the church were various and included World War One and the two accidents in which the master mason Toni Vella broke his legs when he fell from the building site. Architect Mallia later informed Parish Priest Xerri that he did not intend to continue with the project and this was passed on the Architect Guze D' Amato. When D' Amato died he was replaced by Architect Joseph Mizzi from San Lawrenz who stayed for eight years. The last architect to oversee the works on the new church was Joe Ellul Vincenti from Sliema.