Payline

This means that to win anything, you must line up a winning combination on that center payline and on that line only.

Source: wiktionary

Much like bingo, the multiple payline machines give slots players various directions that can turn them into a winner. The single payline machine has one line across the machine, which shows where the reels must line up for a winning combination to be paid. The multiple payline machine, on the other hand, has three or five lines, depending upon the machine, which give players more winning positions on the reels.

Source: wiktionary

The disadvantages in multi-payline machines are that the smaller payoffs are usually very small, much smaller than on one-payline machines, and also that the top jackpot is usually paid only if you line up the proper winning symbols in the correct sequence on the bottom, or third, payline. Or the fifth payline in case of the five-line machines, or the eighth payline in case of the eight-line machines, and so on — basically, if you don't play all the paylines you cannot win the jackpotl

Source: wiktionary

When an Institute indicates a particular percentile payline, it means that Applications with an equal or better (lower) percentile will generally be funded.

Source: wiktionary