Possible Clues:

• Half protested I'm standing for the wrong title
• Mean lad to receive no marks for bad term
• Inapt term actor used to cover errant son
• Chap who's mean about Pierre, say, as inappropriate name
• Unsuitable designation
• Poorly attached handle has no marks, surrounded by tight one
• What's in erratum is no mere verbal infelicity
• Wrong or unsuitable word for a person or thing
• Unfortunate term, as exemplified in public school
• Inappropriate name