Your D7000 is a DX/crop-sensor camera, so it can use both DX and FX Nikon lenses. DX lenses are designed for crop-sensor bodies; FX lenses also work on DX bodies, but DX lenses on full-frame cameras can vignette.

For panoramas, the best lens depends on how you plan to shoot:

• For stitched panoramas, a normal lens is often easier than a wide-angle, because lower edge distortion makes stitching more reliable. A 35mm or 50mm prime can work well, though 50mm on your D7000 gives a narrower field of view, so you’ll need more frames.
• For 360° panoramas with fewer shots, a fisheye is often the better choice. Specialized panorama software can handle fisheye images well. A Nikon 10.5mm DX fisheye is a common option for DX bodies.
• Very wide rectilinear lenses can be less ideal for stitching because their edge distortion can complicate auto-stitching.

So: if you want maximum simplicity and fewer shots for 360° work, look at a DX fisheye. If you want high-resolution stitched panoramas, use a less distorted normal lens and plan to shoot more frames.