1) Testate 2) Testator 3) Willful woman 4) Woman with a will 
n. female form of testator, although distinguishing between genders is falling out of fashion.
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• (n.) A woman who makes and leaves a will at death; a female testator.
A female who creates her will with her desires for the distribution of her estates is known as testatrix
Tes·ta'trix noun [ Latin ] (Law) A woman who makes and leaves a will at death; a female testator. 
The feminine form of... <a target=_blank href='http://www.finance-glossary.com/terms/testatrix.htm?id=1433&ginPtrCode=00000&PopupMode=false' title='Read full definition of testatrix'>more</a>
A female will maker. However, modernly, the word testator is used for both men and women.
[n] - a female testator
testatrix A woman who has made a legally valid will.
noun a female testator
A woman who has made a will.