foul line

noun

1

: either of two straight lines extending from the rear corner of home plate through the outer corners of first and third base respectively and prolonged to the boundary of a baseball field

2

: a line across a bowling alley that a player must not step over when delivering the ball

3

: either of two lines on a basketball court parallel to and 15 feet from the backboards behind which a player must stand while shooting a free throw

Examples of foul line in a Sentence

The ball landed just inside the right-field foul line.

Recent Examples on the Web

While one portion hovered over the foul line, most of the ball appeared to be in foul territory. —Ian Miller Outkick, FOXNews.com, 29 Apr. 2026

The Celtics also have kept him off the foul line, limiting Maxey to nine total free-throw attempts through the first three games. —Zack Cox, Boston Herald, 26 Apr. 2026

Left fielder Alyssa McClure made a diving catch along the foul line with runners at first and second in the third. —Dan Albano, Oc Register, 25 Apr. 2026

Advija was 3 of 15 from the field Friday, though the Spurs did send him to the foul line 16 times. —Jeff McDonald, San Antonio Express-News, 25 Apr. 2026

Word History

First Known Use

1868, in the meaning defined at sense 1

Rhymes for foul line

• affine
• airline
• align
• aline
• assign
• baseline
• beamline
• benign
• bloodline
• bovine
• byline
• canine

Kids Definition

foul line

noun

1

: either of two straight lines running from the rear corner of home plate through first and third base on to the boundary of a baseball field

2

: a line across which a player must not step (as when bowling or shooting a free throw)