front end shimmies when driving, especially noticeable when turning, could it be an unbalanced or worn tire or an axle?

Are you in the snow belt? Driving with snow/ice lodged in the wheel can cause
imbalance. You can simply swap tires to see if the front end problem changes.

The others are right that you have ball joints, tie rod ends, strut mounts,
etc. to check out. Any slop in the front end means trouble.

Bill

klaus is correct.
and the tire is unlikely.

i just fixed a shimmy/wobble that occurred on my car during braking. i thought it was my old rotors, they are 270k+ miles and the pads were well worn. i repaired/replaced the brakes and found a cracked control arm bushing on the front AND a worn out rear-shock mount on the opposite side of the car.
worn/cracked/bad bushings can make all sorts of weird driving things happen.

check for any play from any wheel.
good luck!
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-woodsy; 280k 1995 850 wagon;

Lots of things, but probably not unbalanced which is more noticeable at higher speeds. You will need to jack up the corner of the car. Then you can check for bearing play, steering knuckle, and axle looseness(?). Any one of which can induce tire wear.
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Keeping it running is better than buying new