silver fern sil·ver·fern uncommon noun 1. tropical American fern having fronds with white undersides Synonymssilver fernPityrogramma calomelanos 2. fern of southern tropical Africa having fronds with white undersides Synonymssilver fernPityrogramma argentea Related words Broader terms fern Parts Pityrogramma WordNet 2.1 (Princeton University). WordNet 2.1 Copyright Princeton University. All rights reserved.
