ferromagnetic adj.

before vowels ferr-, word-forming element indicating the presence of or derivation from iron, from Latin ferro-, combining form of ferrum "iron," which is of unknown origin. Possibly of Semitic origin, via Etruscan [Klein]; Watkins suggests "possibly borrowed (via Etruscan) from the same obscure source as OE bræs "brass." Also sometimes especially indicative of the presence of iron in the ferrous state; ferri- indicating iron in the ferric state.

1610s, literal but poetic (Donne), "having the properties of a magnet;" it is attested from 1630s in the figurative meaning "having powers of attraction" (but Donne's conceit also had that in mind), from Modern Latin magneticus, from Latin magnes (see magnet). The meaning "capable of being attracted by a magnet" is by 1837. Related: Magnetical (1580s); magnetics "the science of magnetism" (1786).

She, that should all parts to reunion bow ;

She, that had all magnetic force alone

To draw and fasten sunder'd parts in one ;

She, whom wise Nature had invented then,

When she observ'd that every sort of men

Did in their voyage, in this world's sea, stray,

And needed a new compass for their way ;

[Donne, "An Anatomy of the World"]