[Grammar] For whoever saw a rabbit with a pocket - or a watch?

[kadioguy]

[In Alice in Wonderland]

But when it took a watch out of its pocket she jumped up. For whoever saw a rabbit with a pocket - or a watch?
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What does the "for" mean?

I see it as "(she jumped up) For whoever saw a rabbit with a pocket - or a watch?" (I.e., jump up for something)

Is that right?
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(Source)

 

[tzfujimino]

I'd take that "for" to mean this:
https://www.oxfordlearnersdictionaries.com/definition/english/for_2

 

[tedmc]

Would this be clearer?

She jumped up (a sign of great surprise), at the thought/for the reason that "who would ever have seen a rabbit with a watch in its pocket?".

 

[kilroy65]

MAINLY LITERARY: because

She began to grow nervous, for he had promised to return before nightfall.

(Macmillan)