Like many puzzles I do, this came to me while tooling around looking at different word facts. “Hmmm”, said I, “wonder if I could do that in a puzzle?” As it turns out the answer is yes. Our language is intriguing and we have many things we see all the while that we do not realize are something “special”.
This meta focuses on that. Do not just look for symmetrical theme answers to help you because the description you are seeking is everywhere. You will just have to figure out what the similarities are; but for this group of smarties that should be relatively easy. I am going to give this a Persian rating just because the “thing” is subtle and you will look a lot of places and try a lot of exotic things before you go DOH, that’s it!!!
Kitten
Calico

Persian
Puma
Lion
Al Sisti helped me immensely on this puzzle, making me refine a few things that really upped the quality. I also got a lot of help from lbray53, another of my testers who won’t let me settle for OK. I thank them both.
So off you go on the hunt, hopefully for answers not rabbits
Nudges Friday or anytime by PM
Well this one seems to be in need of at least an early nudge, nothing too blatant I hope:
Early Nudge] Look at what are typically the "themers" and, ironically, compare them to see how they are similar.
More Nudges!
Nudge] If I had wanted to use a mathematical nudge I would have said "If you look at the longest entries you'll be all set"
Push] Would it have been helpful if one of the clues in the puzzle were "Things with 4 different legs and more than one M" - MAMMALS
Shove] You all know I often sneak a graphic nudge into my banner. Well the banner is a picture of Hadrian's Wall in the north of England. This is an amazing construction, running the entire width of the country (73 miles) and of course built entirely by hand from local stone so that, unlike the Great Wall of China, no section is the same as any previous section.
This ought to do it] In a way, you might say the answer you are looking for is uniquely suited for the puzzle!
And yet another..] You are looking for 7 letter word
Still more..] You will get that word via a VERY basic mechanism
Gonna stop here for now..] You may not know the word but if you look it up you'll know why I chose it and why those were the theme answers you needed.
The REVEAL
WOW, this one did NOT go the way I expected. What DID I expect?
Well first of all I hoped you would notice that there were 9 long words and write them down one under another:
IMPERSONAL
STEAMING
COSETTE
OUTCHARGE
GRADIENTS
REPULSION
TSONGAS
AILMENTS
MANUSCRIPT
Then I was sure you would notice that 7 of those words had something in common, i.e. they were all made of non-replicating letters, something the other two long answers were not. Eliminating those words left you with:
IMPERSONAL
STEAMING
OUTCHARGE
GRADIENTS
REPULSION
AILMENTS
MANUSCRIPT
The first letters of which spell the meta answer: ISOGRAM
I think a lot of people had never heard of an ISOGRAM, but it certainly looks and sounds like a word and, if you Google it, you immediately get the definition - a word made of non repeating letters. It was hard to nudge because the mechanism was so simple really. Oh, and by the way if you look you will see that all clues for ISOGRAMS are made of ONLY ISOGRAMS and the clues for Non-ISOGRAMS have at least one Non-ISOGRAM...that is my OCD working overtime.
For a graphic representation of the solve go to: