The triquetra symbol becomes frequent from about the 4th century BC ornamented ceramics of Anatolia and Persia, and it appears on early Lycian coins.

The depiction of the triquetra as interlaced is common in Insular ornaments from about the 7th century.

The symbol has been interpreted as representing the Holy Trinity, especially since the Celtic revival of the 19th century.

In the 1998–2006 American fantasy drama Charmed, that ran on the now-defunct The WB network, the triquetra was prominently used as a symbol on the Halliwells' Book of Shadows, the book of spells, potions, and other information the sisters used to fight evil. The triquetra was also used as a symbol of the Charmed Ones and their collective Power of Three. The triquetra on the Book of Shadows would be seen to fracture and pull apart when their bond was temporarily broken by a demon. It was also featured prominently in the opening credits of each episode throughout its eight-season run. The symbol was also used in the 2018 reboot that ran on The CW.

In the German Netflix series Dark (2017), it symbolizes the caves' closed time loops with each loop being 33 years apart, with the past affecting the future and the future influencing the past. The Triquetra is of significant symbolic value to the time travelers. This symbol can be seen on the Cave's metal door, on the Emerald Tablet, in The Stranger's papers, and in the Sic Mundus photo.

The symbol was also used in the 2018 reboot that ran on The CW.