How many letters does the top answer for “producing or yielding iron.” have?

The most common answer is ferriferous (11 letters).

Crossword clue: producing or yielding iron.

1 answer found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).

ferriferous 11 letters web-def

Producing or yielding iron.

producing metals; yielding metals. 50% similar → metalliferous

producing or yielding milk. 50% similar → lactific, lactifical

yielding or producing wood. 50% similar → ligniferous