Synonyms for Flat-leaf parsley:

n.

flat-leaf parsley (noun)
Petroselinum Crispum Neapolitanum, Italian Parsley.
plant (noun)
Petroselinum Crispum Neapolitanum, Italian Parsley.

Other synonyms:

Italian parsley
Italian Parsley.
Petroselinum crispum neapolitanum
Petroselinum Crispum Neapolitanum.