We don't have synonyms for marygold yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are mangold, marigold and manyfold.
(n) :
Obsolete form of marigold (“the flower”). [Any of the Old World plants, of the genus Calendula, with orange, yellow or reddish flowers.]
(n) :
Obsolete form of marigold (“a million pounds sterling”). [Any of the Old World plants, of the genus Calendula, with orange, yellow or reddish flowers.]
(n) :
Obsolete form of marigold (“the flower”). [Any of the Old World plants, of the genus Calendula, with orange, yellow or reddish flowers.]
(n) :
Obsolete form of marigold (“a million pounds sterling”). [Any of the Old World plants, of the genus Calendula, with orange, yellow or reddish flowers.]