marked by the characteristics of an earlier period; antiquated:
an archaic manner; an archaic notion.
(of a linguistic form) commonly used in an earlier time but rare in present-day usage except to suggest the older time, as in religious rituals or historical novels. Examples:
thou; wast; methinks; forsooth.
forming the earliest stage; prior to full development:
the archaic period of psychoanalytic research.
(often initial capital letter) pertaining to or designating the style of the fine arts, especially painting and sculpture, developed in Greece from the middle 7th to the early 5th century b.c., chiefly characterized by an increased emphasis on the human figure in action, naturalistic proportions and anatomical structure, simplicity of volumes, forms, or design, and the evolution of a definitive style for the narrative treatment of subject matter.
Archaic is used as a label in this dictionary for terms and definitions that were current roughly as late as 1900 but are now employed only as conscious archaisms, as described and exemplified in definition 2 above. An archaic term is generally more recognizable, as when encountered in literature, than one labeled Obsolete.