1a reddish- or yellowish-brown flaking coating of iron oxide that is formed on iron or steel by oxidation, especially in the presence of moisture:paint protects your car from rust figurativethe MPs are here to scrape the rust off the derelict machinery of government
2 [usually with adjective or noun modifier] a fungal disease of plants which results in reddish or brownish patches.
The fungi belong to Puccinia and other genera, order Uredinales, class Teliomycetes
The fungi belong to Puccinia and other genera, order Uredinales, class Teliomycetes