A sentence from a dictionary: "I am afraid..."

[Tom]

Hi

The following is a sentence from a dictionary in the entry of dinner. No further context. Could you please explain it to me?

[Yankee]

Hi Tom

I think the sentence is a little odd, but I would say that it means that you will have to set your plate on you knees and eat. (Maybe you can't set your plate down on a table because there is no room at the table -- i.e. you can't eat at the table.)
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[Tom]

[Yankee]

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'On your knees' generally means that you are kneeling, Tom.
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[Tom]

[Yankee]

Hi Tom

I understand the context, but as I said, I find the original sentence a bit odd.

If you said "You will have to eat your dinner on your knees", I would probably understand that I will have to kneel rather than sit when I eat dinner. That is probably why the author of the sentence decided not to use 'on', and instead used 'off'.

With 'off' in the sentence, yes, it might also be understood as you described. This is another good example of what an important role context can play.

That's the best I can do, Tom.
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