rust of iron

remove, prune away, carry off, take away

rust

insignificant; meaningless; not worth attention

(archaic) iron / (figuratively) something extremely strong

iron

iron, the metal and the metallic chemical element / (more generally) steel / short for 鉄砲 (teppō, literally “cannon”, but in this case, refers to the poisonous fugu blowfish or dishes made from it)

reason / origin / history / oral tradition

(colloquial, informal) good / (colloquial, predicative only) enough, not wanted any more

committee