According to the Cambridge English Dictionary if something is sacred it is considered to be holdy and deserving of respect, especially because of a connection with a god..
"The purpose of this paper is to examine the symbolic value of religious buildings in the United States. It will focus particularly on places of worship and the theologies conveyed by them in an ever-changing socio-religious landscape."
The Ark is the "The repository of the sacred scrolls of the Torah (The Five Books of Moses). Though the Holy of Holies in the Temple in ancient Jerusalem was out of bounds to everyone, except the high priest on Yom Kippur (The Day of Atonement), the synagogue Ark is accessible to all ... "
Judaism
"Visit Rome, Spain, Budapest and New York exploring how the Jews, scattered to the four corners of the Earth, found refuge and how they expressed themselves in art and architecture."
"The idea of "sacred space" has been discussed frequently in the study of religion, both the ways in which faith communities engage with sacred space, as well as how different religions define and authenticate their sacred spaces."
" Using the Qur'an as a mould, two broad definitions of sacred space are explored and contextualised within the Islamic tradition. The entire process of sacralisation of space is reflected in the history of the Ka'bah, as recorded in the Qur'an."
Islam
"This program visits the Djenne Mosque the largest dried-earth building in the world in Djenne, Mali. From Mali it moves to India to look at the Jama Masjid mosque in Delhi. Istanbul, in Turkey where Europe meets Asia became a showcase of Islamic art and architecture, most evidently in the Blue Mosque and the Suleymaniye Mosque. Also looks at Spain and New York."
"The paper aims to examine the meaning of sacredness in such a religion as Buddhism where there is no idea of God or any supernatural being."
Buddhism
"The Maha Bodhi temple of Bodh Gaya is one of the most important places of worship for Buddhists, marking the holy spot of the enlightenment of Gautama Siddhartha. Next, Christy visits Sanchi in Central Madhya Pradesh, which became the centre of Buddhist art and architecture between the 3rd and 7th centuries AD."
"A Hindu place of worship is called a mandir or temple. A temple is dedicated to a particular god or goddess (deity). The temple is the god's home on earth."
Hinduism
"Shot in 36 distinct locations in 14 countries, combining religion, art, history and travel, this documentary series explores how six major world religions have expressed the spiritual yearnings of the faithful in art and architecture."
"Sacred, beautiful, and universal were the qualities of liturgical music set out by Pope St. Pius X in his motu proprio of 1903. These are, however, qualities that pertain to every aspect of liturgy, including vestments, even sermons, but particularly architecture. The architecture of a church can convey the sense of order and beauty that is essential to its sacredness."
Christianity
"In search of the expression of Christianity through art and architecture, presenter Christy Ogwen journeys through Ireland and then on to Rome, Istanbul, Switzerland, Ethiopia and France."