Tantrika is a Sanskrit word that means “relating to Tantra.” Tantra is a Hindu spiritual practice (sadhana) based on religious and mystical texts devoted to goddess worship and shakti (divine feminine energy). It is also the name used to describe this collection of texts (Tantras).
Tantrika, generally, describes a scholar immersed in the study of science or a system. More specifically, it can be defined in several ways:
As a noun — someone who adheres to the sadhana of Tantra.
As an adjective — describing the Tantras (texts) and their doctrines, or the rituals of worshiping the goddess within.