From Longman Dictionary of Contemporary Englishbe made of sterner stuffbe made of sterner stuffto have a strong character and be more determined than other people to succeed in a difficult situation Ann, made of sterner stuff than I, refused all offers of help. → stern
Examples from the Corpus
be made of sterner stuff• But Bastide was made of sterner stuff.• But it seems to us that hypocrisy should be made of sterner stuff.• In the years separating the two Great Wars women were made of sterner stuff.• Miller seemed about to choke on his drink, but Floyd was made of sterner stuff.• The visitors seem to be made of sterner stuff.• This time, however, the opposition was made of sterner stuff.• The female characters, too, are made of sterner stuff than the quick-witted schemers of Figaro. 