Formfehler {m} - defect in form; error of form; formal defect; formal error; formal irregularity 
Formfehler {pl}  - defects in form; errors of form; formal defects; formal errors; formal irregularities Formfehler eines Vertrags  - formal defect in a contract/treaty Formfehler eines Testaments  - formal defect in a will einen Formfehler beseitigen  - to correct an error of form einen Formfehler heilen  - to cure a defect of form