Searching Wordfind for a word starting with Z, I found the following words accepted by Scrabble:
zebra – any of several fleet black-and-white striped African equines (“A horse in striped pajamas” in the song I learned from watching Captain Kangaroo, but larger than the horse; one tried to bite the inspection sticker off our windshield at the Natural Bridge Wildlife Park when we stopped to gawk.)
zoa – any of the individuals of a compound organism; sing. zoon. (An epiphanic [Well, d’oh] moment when I realized how the word protozoa came to be. Once upon a time I knew that.)
zed – the British spoken form of the letter z. U.S. word zee (Zed was used by Dorothy L. Sayers’ character Lord Peter Wimsey, as played by Ian Carmichael, the only actor who has done justice to the role.)
It’s zed that fits today, the final day of the April challenge.
I shouldn’t post at all, since I bailed out of the challenge after R. On day S, I could have written that I’d run out of steam, but I didn’t think of it until Day U. Posting wouldn’t have been fair.
This Zed post isn’t fair either, but it has a purpose: to thank the bloggers who read my challenge posts. While my energy was at low ebb, I fell behind in reciprocal reading, but I have your addresses and will make it up. And then some.
It was a pleasure blogging with you. I look forward to April 2019, when I will again sign up to write.
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The etymology of zed is worth noting:
c.1400, from Middle French zede, from Late Latin zeta, from Greek zeta, from Hebrew
zayin, letter name, literally “weapon”; so called in reference to the shape of this latter in ancient Hebrew. U.S. pronunciation zee is first attested 1670s. Other dialectical names for the letter are izzard, ezod, uzzard, and zod.
All my life I’ve heard the phrase “from A to izzard,” but I didn’t know izzard is officially related to Z.
Source: Online Etymology Dictionary, © 2010 Douglas Harper
“zed”. Online Etymology Dictionary. Douglas Harper, Historian. 30 Apr. 2018. Dictionary.com http://www.dictionary.com/browse/zed.
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Other Z posts appear at AtoZ.
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Image of zebras by COFFEE under CC0 via Pixabay
Image of Cryptosporidium parvum Protozoa ooycysts by Geoffrey Whiteway under CC0 via Free Range Stock
Kathy Waller 
I have never heard of the phrase A to izzard.
I find myself using “za” all the times when I play Words With Friends, a scrabble variant. Apparently it is short for pizza. Never a word I would use in real life. I do use zed though as Australian English is similar to British English. I agree that Ian Carmichael was terrific as Lord Peter. I liked him as Siegfried in “All Creatures Great and Small” too.
Regards
Anne
fellow A to Zed-er (do you say Zee-er? I definitely say zed)
https://ayfamilyhistory.com/2018/04/30/z-is-for-zacharie/
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S may have run out of steam.. z may be the end…. but the fun part is that A in April will come Again… and that you are an Author And A lof of other things that Allow for the complexity of All letters.
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