"Siderated" is a relatively uncommon word used to describe something that has been made or treated with iron. There are several synonyms which can be used in place of "siderated". These include "ferrous", which refers to anything that contains iron or has been treated with it; "ironed", which means something has been flattened or smoothed by being pressed with a hot iron; "steely", which can be used to describe something that is hard, cold, or firm like iron; and "ferruginous", which means something is rusty or iron-like in appearance. By using synonyms like these, writers can avoid repetition and create more descriptive and engaging texts.