1. iron (Fe)

noun (common) (futsuumeishi)

2. steel

noun (common) (futsuumeishi)

3. iron (will, discipline, lady, etc.)

noun (common) (futsuumeishi) nouns which may take the genitive case particle 'no'

4. railway

noun, used as a suffix noun (common) (futsuumeishi) noun, used as a prefix abbreviation

5. railway enthusiast

noun, used as a suffix colloquial