first down noun
plural first downs
plural first downs
Learner's definition of FIRST DOWN
[noncount] American football
: the first of a series of usually four downs in which a team must gain 10 yards to keep the ball（四次10码进攻中的）第一次进攻，首攻，首档 also [count] : the right to start a new series of downs after a gain of 10 or more yards（进攻方前进10码后所获得的）新一轮四次10码进攻权，首攻机会