What does "consound" mean?

Solution 1:

"Consound it" means the same thing as "confound it".

My guess is that the interjection "confound it" was thought to be too strong in Hannibal, Missouri, at the time of Mark Twain's childhood. So people changed the pronunciation slightly to avoid using "bad words". (I don't see anything objectionable in "confound it", but maybe it was perceived as a euphemism for "damn it" that was somehow too close to the original.)

When Mark Twain was editing his original draft of Huckleberry Finn, he changed at least one instance of "consound it" to "confound it". See this link. Tom Sawyer contains both "confound it" and "consound it".

Solution 2:

Consound it, concern it and consarn it are all minced oaths for confound it, which is itself a minced oath for damn it, in turn arguably a minced oath for God damn it.

Solution 3:

I think it is just a general interjection ... used in place of a profanity that "polite society" would disapprove.

My father used to say, "Confound it".