Portuguese

Adjective

cáustico m ‎(feminine singular cáustica, masculine plural cáusticos, feminine plural cáusticas, comparable)

1. caustic (capable of destroying organic tissue)
2. (figuratively) caustic (very critical or unpleasant)

Noun

cáustico m (plural cáusticos)

1. caustic (substance which burns, corrodes or destroys organic tissue)

Spanish

Adjective

cáustico m ‎(feminine singular cáustica, masculine plural cáusticos, feminine plural cáusticas)

1. acrimonious; caustic