“servant...slavegirl.” The Hebrew uses two different word for “servant” here that are difficult to represent in English, because generally both are used of slaves or servants. The first is shiphchah (#08198 שִׁפְחָה), which refers to a slave or servant, and the second is amah (#0519 אָמָה), which refers to a woman who is not free in one sense or another, generally a female slave, but perhaps, for example, a concubine. Usually the difference between them is so subtle that they are both brought into English as “slave” or “servant” depending on the context. Also, women would sometimes use these terms as an act of self-abasement to portray a humble attitude (cp. 2 Sam. 20:17).
However, the fact the woman of Tekoa uses them both here in the same sentence suggests that she is deliberately playing them off against one another. Although it may be the case that the sentence composition is just for style, as some scholars suggest, the NET text note is more likely correct in suggesting that a lord might have some level of obligation to the amah servant. This would explain why the woman used amah in the context of the king acting on her request. In the latter chapters of 2 Samuel, amah only occurs in 2 Sam. 14:15, 16; 20:17).