Kalfa (Turkish for 'apprentice, assistant master') was a general term in the Ottoman Empire for the women attendants and supervisors in service in the imperial palace.
The titles usta and kalfa belong to the terminology of Ottoman guild organization and other hierarchically-organized corporate bodies.
Legally slave girls, these women—depending on their rank—could wield considerable authority and influence in their duties and were generally treated with much respect by lower-ranking attendants in the harem as well as by members of the imperial family.
[1] Among craftsmen the term had a similar rank: that of a junior master yet to graduate to usta status[2] and open his own shop.
[1] Notable women traditionally addressed as kalfas include Cevri Kalfa, a slave girl who saved Sultan Mahmud II's life and was awarded for her bravery and loyalty and appointed hazinedar usta, the chief treasurer of the Imperial Harem, which was the second-most important position in the hierarchy.