Curious...

[Mjwedding]

We have this vine ivy growing in a part of our backyard, and we thought it was poison oak. But, I'm not entirely sure. We haven't removed it fully, but I am unfamiliar with this type of vine.

Any help.

 

[NatalieW]

It doesn't look like poison oak to me.... poison oak doesn't have those open dips in the leaves. poison oak has 3 individual leaves on a stem.

 

[Marck]

I am going to tentatively identify this single leaf as from the Cupseed Vine (Calycocarpum lyonii) in the Moonseed Family (Menispermaceae). The leaves of Cupseed are remarkably variable, having any number from 3 to 7 primary lobes. and with margins that can vary from smooth to wavy, to toothed, to secondarily lobed.
This leaf seems to fall into that range of variation, but I would like to see more leaves, preferably still attached to the stem.

I often wish that OPs would take more pictures or better pictures, or give more geographic and habitat information.
This is especially true in this case. Yes, I know it is five years later, but if the OP can supply any more information, please do not hesitate to respond to this post.