A sharp drop off in elevation or the bottom contour. Some channels cut "V" shaped cuts though the land and others cut "U" shaped cuts though the land. These cuts are caused by errosion due to running water. Later when the area is flooded the channels remain. Areas become flooded after the river is damned.
A channel can be winding and meandering and have inside and outside bends.
Also a break can be found along the shorelines or around underwater humps or islands. A cliff face can also be a break in elevation.
Structure can consist of stumps, rocks, or changes in bottom compostion that are found on the lake bottom.
If you can find some structure along a break line then you may have a great fishing spot depending on many other factors such as it being an isolated stump or where along the break line the stump is located.
A break line can be a change in water clarity also. Such as a mudline. A weedline along a breakline can also be called a breakline. As the bottom gets deeper along a dropoff the weeds can no longer get enought sunlight to grow and will die off in the deeper water. The end of the weed growth can be sharp and form a wall of sorts. That wall is a good place to catch fish as it provided the fish cover to ambush prey from and also gives them oxygen and cover from sunlight.
I am sure that there are other definations of a break line that others will tell you.
Originally Posted by Tugaloo