We don't have synonyms for first down yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are fight down and first born.
(n) :
(American football) The first play in a series that has a maximum of four downs.
(n) :
(American football) The act of getting a first down by advancing the ball more than ten yards ahead of the field position where the team took possession.
(n) :
(American football) The first play in a series that has a maximum of four downs.
(n) :
(American football) The act of getting a first down by advancing the ball more than ten yards ahead of the field position where the team took possession.