"Ich werde ihn Mittagessen nennen."
I think the problem here is once again that the German 'ihn' can refer to any masculine noun like an apple ('Der Apfel'). So you can say 'Ich habe nur einen Apfel. Ich werde ihn Mittagessen nennen' - 'I only have an apple. I'll call it lunch'. Unfortunately, duo seems to mechanically translate 'er' to 'he' and 'ihn' to 'him' which often doesn't make any sense in English. To justify duo's translation we'd have to talk about fables or cannibals here.
We do have a similar slang expression, for example, "If he tries that, she'll have him for lunch," meaning that if he does what he proposes to do, . . . well, the rest is probably obvious.
Yes, but the German sentence wouldn't be interpreted figuratively but literally. A bit scary...
It is. Nonetheless, I plan to treasure the sentence and use it on an occasion of my choosing. ;-)
Right, so maybe it's like calling a cab? Am i right? Could nennen be used in that sense?