early 13c., "a cover or covering" (earliest reference is to bedcovers), from Old French coverture (12c.) "blanket; roof; concealment," from Latin *coopertura, from past participle stem of cooperire "to cover" (see cover (v.)). From late 14c. as "a protective device, a refuge." In old law, "the state of a married woman considered as under the power and protection of her husband" (1540s).
At common law coverture disabled a woman from making contracts to the prejudice of herself or her husband without his allowance or confirmation. [Century Dictionary]