teething troubles /ˈtiːðɪŋ ˈtɹʌb(ə)lz/ noun[plural only]1 •Problems that are to be expected with any new and untried product, system, or venture.He admitted that in their early days these units suffered a number of teething troubles, which, he said, "one may now look back upon with some wonder", as their causes were not hard to find. — 1961
