Definition of 'Gain'
An increase in the value of an asset or property. A gain arises if the selling or disposition price of the asset is higher than the original purchase or acquisition price. This positive difference between the sale price and purchase price is referred to as the gross gain; if transaction costs such as commissions and other expenses are considered, this would be a net gain. A gain may either be realized, i.e., when the asset is actually sold, or unrealized, i.e., a paper gain. Another important distinction of a gain is that it may be taxable or non-taxable.
Investopedia explains 'Gain'
In most jurisdictions, realized gains are subject to capital gains tax. However, if the gains accrue in a non-taxable account - such as an Individual Retirement Account in the U.S. or a Registered Retirement Savings Plan in Canada - gains will not be taxed.
For taxation purposes, net realized gains - rather than gross gains - are taken into consideration. In a stock transaction in a taxable account,the taxable gain would be the difference between the (higher) sale price and purchase price, after taking brokerage commissions into consideration.