Reselling vs. Dropshipping

I am trying to understand these different terminologies. Let's say I buy an xbox controller from newegg and resell it in my store at 15% markup. A customer places on order on my site, I go to newegg and place their order and have the shipping address my customer's address.

Is that considered dropshipping, even though I am not buying from a whoelsaler?

What is the difference between reselling from a wholesaler, and reselling from another retailer?

A wholesaler buys inventory and then resells it.

A dropshipper sells inventory, has the maufacturer (or whoever) ship the product to the buyer. The dropshipper never takes possession of the goods.

Not correct - dropshipper mostly stocks merchandise and sells it to reseller. But instead of sending products to reseller he sends products directly to his customer (dropshipping service).