Not sure I understand? Use it without the leaf.
Perhaps the leaf has no apron. That was done in lower end tables, in which case you could cut the leaf. But if the leaf has an apron...don't try it...
Either use the table as is until you have a large enough place, or don't buy it.
Linda C

Thanks, Linda C, for your quick response. I would imagine the leaf has an apron (not skirt -- sorry). I would like to be able to use a leaf sometimes, but this one's just too big.

Thanks for setting me straight -- I know you are right!

"Perhaps the leaf has no apron. That was done in lower end tables, in which case you could cut the leaf. But if the leaf has an apron...don't try it... "

Table leaves without aprons are not just on "lower end tables."

You can cut the entire leaf narrower, apron and all with the correct tools (think bandsaw).

It just needs enough clearance to cut everything.

You will need to put some kind of finish on the cut edges to prevent warping.

If it's a veneer piece, lots of extra care has to be taken or there are splinters in its future.
You could make a leaf any size you wanted from a piece of pine or plywood, if you used a tablecloth. Then the value of the table would be preserved. It must be some leaf if you can remove 10 inches and still have it useful. I could see having a cabinetmaker divide it exactly in half, giving you the most flexibility, and still keeping the table's value, because it would be cut with the proper equipment and skill. A 14" tablesaw with a zero-clearance insert could slice right through this, including the apron. He would have to pre-score any elaborate veneer on the apron, because one side of it would still splinter pretty badly, unless he stopped the cut, flipped the leaf end for end, and cut in the opposite direction. The cut would be dressed with a sanding block &/or sharp hand-planes.
Casey