What is the meaning of eat up?

verb

• Finish eating all the food on one's plate or on the table.
  • usage: "She polished off the remaining potatoes"
  • synonyms: finish, polish off
• Use up (resources or materials. )
  • usage: "this car consumes a lot of gas"; "We exhausted our savings"; "They run through 20 bottles of wine a week"
  • synonyms: consume, use up, eat, deplete, exhaust, run through, wipe out
• Enclose or envelop completely, as if by swallowing.
  • usage: "The huge waves swallowed the small boat and it sank shortly thereafter"
  • synonyms: immerse, swallow, swallow up, bury