The leg side, or on side, is a particular half of a cricket field.
A cricket field may be notionally divided into two halves, by an imaginary line running down the middle of the pitch, through the middle stumps, and out to the boundary in both directions. The leg side is the half of the field behind the on-strike batsman, when the batsman is in normal batting stance.[1] Which half of the field is the leg side therefore depends on whether the on-strike batsman is right-handed or left-handed. The other half of the field, in front of the on-strike batsman, is called the off side.[2]
From the point of view of a right-handed batsman facing the bowler, it can also be thought of as the left-hand side of the cricket field,[3] and from the bowler's perspective, it is the right-hand side. With a left-handed on-strike batsman, the leg side is to their right, and from the bowler's perspective, it is the left-hand side. From the on-strike batsman's perspective, it is therefore the side of the field corresponding to their non-dominant hand.
In the picture, the right-handed batsman, facing the bowler in normal batting stance, has his legs more on the right side of the picture, the leg side. If the bowler bowls the ball down that side of the pitch it will be "on" the batsman's legs, the on side.
Leg-side - The area of the pitch behind the batsman's legs
The field is spoken of as being divided lengthwise into off and on, or leg, sides in relation to the batsmen's stance, depending upon whether he bats right- or left-handed; the off side is the side facing the batsman, and the on, or leg, side is the side behind him as he stands to receive the ball.
legside - the part of the field to the left of a right-handed batsman as he faces the bowler