Possible Clues:

• Get in the way
• Obstruct, create obstacle
• Slow
• Obstruct, hold up
• The way to get in the way of something in the way a back bit
• Obstruct; nearer the back
• Obstruct or hold back
• This part of the backside won't help at all
• Hold up from coach in derailment
• Not for the sound of it, but there's no help for it