The phrase references puzzles where answers are names of players who play on the offensive or defensive line in professional American football’s National Football League. These puzzles test knowledge of sports figures, often requiring familiarity with both current and past players. As an example, a clue might be “New York Giants defensive end,” with the answer being “Osi Umenyiora,” assuming the puzzle was published when he was a prominent player.
The appeal lies in its blend of general knowledge, sports acumen, and wordplay skills. Completion requires not only awareness of athletes but also an understanding of crossword conventions, such as abbreviations, alternate spellings, and common fill words. The challenge provides mental stimulation and a sense of accomplishment upon solving. Historically, sports-themed crosswords have been a staple in newspapers and puzzle books, indicating enduring interest in the intersection of trivia and linguistic challenges.