The spread is the difference between the Bid (Sell) price, and the Ask (Buy) price. It is the commission the broker charges on every position.
eToro provides two-way (Buy and Sell) prices to its customers. The price at which a customer 'buys' is the higher of the two prices and is commonly referred to as the 'offer' (or the Ask) price. Conversely, the price at which a customer 'sells' is the lower of the two prices and is commonly referred to as the Bid price.
For example, if the bid is 1.2636 and ask price is 1.2638, the Spread is the difference between the two: 2 pips.