"Take French leave" is a colloquial phrase that means to leave a gathering or event without saying goodbye or without permission. Other similar phrases to "take French leave" includes "abscond," "slip away," "make a break for it," "depart unannounced," or "ghost." These phrases emphasize the stealthy, sudden departure without drawing attention. Furthermore, "take a powder," "hit the road," "skedaddle," and "escape" could also be used as synonyms for "take French leave." These phrases are commonly used in informal situations and convey the idea of leaving abruptly or without notice. However, it is not advisable to take French leave in formal settings or professional circumstances as it may come across as impolite or unprofessional.