burden

noun
  1. A heavy load that is difficult to carry, either physically or metaphorically. noun
    The backpack was a burden on his shoulders during the long hike.
    She felt the burden of responsibility as the sole provider for her family.
  2. A duty or responsibility that causes worry, difficulty, or hard work. noun
    The burden of proof lies with the prosecution in a criminal case.
    Managing the entire project became a significant burden for her.
  3. To load heavily or oppress with a burden. verb
    He was burdened with debt after the business failed.
    The new regulations burdened the company with additional costs.