Q: Does "head" have the same meaning in the following two sentences?

Under the head of minor Roman poets.

They tracked him back toward the head of the stream.

A: different meanings

Q: Does "purchase" have the same meaning in the following two sentences?

To purchase land, to purchase a house.

The family purchased a new car.

A: the same meaning

Q: Does "refund" have the same meaning in the following two sentences?

If you find this computer for sale anywhere at a lower price, we'll refund you the difference.

Please refund me my money.

A:
the same meaning