Definition of ferrogallic in US English:

ferrogallic

adjective

historical
  • 1Designating inks made by adding an iron salt to gallic, tannic, or gallotannic acid.

  • 2Designating a process for producing dark-line images or photocopies using paper sensitized with a solution containing an iron salt and developed with gallic, tannic, or gallotannic acid.

Origin

Mid 19th century.

Pronunciation

ferrogallic

/ˌfɛrə(ʊ)ˈɡalɪk/