In Symbols of Transformation, Carl Jung explores the dynamic relation between the masculine and feminine poles of the psyche. This relation is revealed in images of “sacred cohabitation”. One such image is the Lingam and Yoni. Jung says:
“The motif of continuous cohabitation is expressed in the well-known lingam symbol found everywhere in Indian temples: the base is a female symbol, and within it stands the phallus.”
Lingam is from the Sanskrit लिङ्गं ‘mark.’ ‘sign,’ or ‘inference, (wikipedia). Yoni is from the Sanskrit: योनि word meaning ‘womb.’ As the two primary poles of being the yoni and phallus illustrate the most basic polarity of being: the eternal ground of being and the signifier, sign, or mark which reveals the nature of this ground.
Carl Jung, Cw 5, Symbols of Transformation (in US Pubic Domain, first published 1912)