IPA: //təˈtuːɪst//
KK: /tæˈtuːɪst/
A person who creates designs and applies tattoos to the skin of clients.
The tattooist carefully inked the intricate design on her arm.
Tattooist is formed from "tattoo" (from Tahitian "tatu", meaning to mark or strike) and "-ist" (meaning a person who practices or is concerned with something). A tattooist is a person who marks the skin with designs or art.
Imagine someone who 'marks' ('tatu') the skin with art — that's what a tattooist does.