Tolkien does not separate the elements of this word, does not say that Bilbo “broke his fast”, or any variation thereof.  In fact I can’t find any instance of “fast” as “to abstain from food”, nor any clear case of “breakfast” as a verb (possibly in 07.122).  We do have that very important hour, “breakfast-time“, which has its own word and which poor English can only render with a hyphen.   I wonder if there’s also a special word for second-breakfast-time.  I note that there are rather more mentions of breakfast than of dinner.

• 01.006 and Bilbo Baggins was standing at his door after breakfast
• 01.022 He had only just had breakfast,
• 01.096 and breakfast to be thought fierce.
• 01.140 I will give you a good breakfast before you go.’
• 01.141 and breakfast.
• 01.142 After all the others had ordered their breakfasts
• 01.142 and cook everybody else’s wretched breakfast.
• 02.001 and hurried breakfast.
• 02.002 Then he had a nice little breakfast
• 02.002 to a nice little second breakfast
• 02.003 and here you are having breakfast,
• 02.019 leaving his second breakfast half-finished
• 02.035 and less for breakfast.
• 02.037 less breakfast,
• 02.063 a perfectly beautiful breakfast for you,
• 02.116 By that time they felt like breakfast,
• 07.001 nor tea nor toast nor bacon for his breakfast,
• 07.004 and late breakfast on the lawn afterwards;’
• 07.109 or there will be no breakfast left for you.’
• 07.110 Breakfast!’
• 07.110 Where is breakfast?’
• 07.111 though we found breakfast laid as soon as we went out.’
• 07.115 I haven’t had a bite since breakfast.’
• 07.122 So they all went to breakfast with him.
• 07.146 He had gone just inside the forest after breakfast
• 08.074 with no hope of any breakfast to revive him.
• 13.052 if there is any breakfast to have.
• 13.056 and more climbing without breakfast!
• 13.056 I wonder how many breakfasts,
• 13.059 I would give a good breakfast to know.
• 13.064 and had such a breakfast as they could,

“fast, v.2.” OED Online. Oxford University Press, March 2016. Web. 10 March 2016.

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