The same definition appears in Lisān al-ʿArab.
Al-Muʿjam al-Wasīṭ—compiled by a committee of scholars under the supervision of the Arabic Language Academy—states:
“Al-khimār: anything that covers. From this comes a woman’s khimār, a cloth with which she covers her head; and likewise the ʿimāmah (turban), for a man covers his head with it and winds it beneath the chin.”
These explicit statements from the lexicographers establish that a woman’s khimār is to her what the turban is to a man. Just as the unqualified word “turban” does not mean that a man’s face is covered, so too the unqualified word “khimār” does not mean that a woman’s face is covered.
On this understanding the scholars—exegetes, hadith authorities, jurists, linguists, and others, early and late—have all proceeded. I have examined the words of more than forty of them, whose exact quotations I recorded in the study mentioned in the introduction, and every one of them confined the definition of khimār to the head, not the face. Are these eminent masters—whose followers are never left in misery—all mistaken, O Shaykh, while you alone are right?