Related Clues:

• It's often heaved
• It might evoke pity
• Reaction to a bad pun
• Beginning of of relief?
• Haunted house sound
• Expression of weariness
• Ululate
• Bellyacher's emission
• Charlie Brown utterance
• Weariness giveaway
• Ululation
• Exhale wistfully
• Sound of sorrow
• Laugh heartily
• React to something hilarious