Within the Śrī Kula tradition of Tantrism, the Śrī Yantra is the visual equivalent of the Śrī Vidyā, a mantra of fifteen syllables. Each syllable represents a goddess who is located within the Śrī Yantra.
"Śrī Yantra." The Concise Oxford Dictionary of World Religions. . Encyclopedia.com. (December 19, 2018). https://www.encyclopedia.com/religion/dictionaries-thesauruses-pictures-and-press-releases/sri-yantra
"Śrī Yantra." The Concise Oxford Dictionary of World Religions. . Retrieved December 19, 2018 from Encyclopedia.com: https://www.encyclopedia.com/religion/dictionaries-thesauruses-pictures-and-press-releases/sri-yantra