Clue: Old lady's maid is a sizeable American, one needing leading liposuctionist (7)
Answer: ABIGAIL
Explanation: Definition: Old lady's maid
A BIG A[merican) + A +L[iposuctionist]. (I don't like "leading [X]" as "first letter of [X]") Traditional name for a lady's maid, perhaps originally from King David's wife Abigail in 1 Sam. 25:25, who describes herself as his handmaid when she first meets him; also the name of a character in the Jacobean comedy The Scornful Lady