lamb

• lamb
• 1 [countable] a young sheep
• 2 [uncountable] the meat of a young sheep[↪ mutton]:
• roast lamb
• a leg of lamb
• lamb chop/cutlet/stew etc
• 3 [countable] spoken used to talk to or talk about someone who is gentle and lovable, especially a child:
• Ben's asleep now, the little lamb.
• 4

   like a lamb to the slaughter

  used when someone is going to do something dangerous, but they do not realize it or have no choice
• 5

   like a lamb

  quietly and without any argument:
• Suzie went off to school like a lamb today.

• ➔ mutton dressed as lamb

   at mutton (2)

Definition from the Longman Dictionary of Contemporary English
Advanced Learner's Dictionary.