Loss: Loss is an accounting concept, the exact opposite of profit, normally the bottom line of the Income Statement, which is also called Profit or Loss statement. Start with sales, subtract all costs of sales and all expenses, and that produces profit before tax. Subtract tax to get net profit. If the end result is negative, then instead of profit it is called loss.
Profit or Loss:
Also called Profit and Loss statement. An income statement is a financial statement that shows sales, cost of sales, gross margin, operating expenses, and profits or losses. Gross margin is sales less cost of sales, and profit (or loss) is gross margin less operating expenses and taxes. The result is profit if it's positive, loss if it's negative.