Archaic devoirs refer to outdated or old-fashioned obligations or responsibilities that one is expected to fulfill. It can also mean a sense of duty or loyalty that is no longer relevant to modern times. Some synonyms for this phrase include antiquated duties, obsolete expectations, outdated obligations, and traditional responsibilities. These terms suggest that the obligations are no longer relevant to contemporary life, but are relics of the past that are still somehow expected to be carried out. The phrase is often used to describe societal norms or cultural traditions that are no longer relevant or practical, but are still upheld in some way.