We do already have mouthful, since we broadly didn’t lemmatize in the first go-round, but now that I’m adding common words, here it is again in context of other mouths!

• 1.090 who was wagging his mouth
• 1.100 and when Bilbo tried to open his mouth to ask a question,
• 1.100 till Bilbo shut his mouth tight with a snap.
• 1.110 so that he forgot to keep his mouth shut.
• 2.046 “Shut yer mouth!”
• 2.059 “He wouldn’t make above a mouthful,”
• 2.103 so shut yer mouth!” said Bert.
• 4.034 with his mouth open.
• 5.033 Mouthless mutters.
• 5.056 in his mouth;
• 5.130 The cry brought Bilbo’s heart to his mouth,
• 5.148 Bilbo’s heart jumped into his mouth.
• 7.092 in their mouths,
• 7.153 and put his hands to his mouth
• 8.142 At that Thorin shut his mouth
• 9.003 and at the far end were gates before the mouth of a huge cave
• 9.018 beyond the steep slope out of which the main mouth opened.
• 9.026 in his mouth,
• 10.006 There it had a wide mouth with stony clifflike gates at either side
• 10.007 Not far from the mouth of the Forest River
• 11.038 a yawning mouth leading