XYZ

X

xanthrocroid
492; Having a light complexion and light hair. (Scandinavian)

X.O.
113; Executive Officer

Y

Ymir
128; In Norse mythology, Ymir was the founder of the race of frost giants and an important figure in Norse cosmology. He formed from the ice of Niflheim, where it met with Muspel's heat and melted. Giants came forth from Ymir's body while he slept. His legs spawned a man and a woman, who came out of his body through the armpits.

The cow Audumla had four udders of milk which fed Ymir. Audumla licked hoar frost and salt from ice, eventually forming Buri, who then fathered Bor, father of Odin, Vili and Ve.

Odin and his brothers killed Ymir. Only two giants survived the flood of Ymir's blood: Ymir's grandson, Bergelmir (son of Thrudgelmir), and his wife. Odin and his brothers used the body to create earth. His flesh filled Ginnungagap; his hair became trees; his eyebrow became Midgard; his bones became mountains; his teeth and bone fragments became stones; his blood became lakes and seas. Ymir's skull became the sky, with four dwarves holding it up. Maggots from his flesh became the race of dwarves.

His name is cognate to Yama of Hinduism. From LaborLawTalk -- really!

Yenisei watershed
143;

Ynglingasaga
133; The Ynglinga saga was originally written in Old Norse by the Icelandic poet Snorri Sturluson about 1225. He based it on an earlier Ynglingatal which is attributed to the Norwegian 9th century skald Þjóðólfr of Hvinir, and which also appears in Historia Norwegiae.Wikipedia entry; The Full Text

Young, Will
490;

Yutts, Clovis
179; KKK member; "Yutz" is a Yiddish word meaning a hapless, clueless, annoying socially clumsy guy.

Yzhitza
714; woman in Vienna;

Yz-les-Bains
931; French: "the baths at Yz"; "the Anarchist spa of Yz-les-Bains, hidden near the foothills of the Pyrenees, among steep hillsides"; "one of the few places on the continent of Europe where a sober Anarchist could find a decent Crocodile — equal amounts of rum, absinthe, and the grape spirits known as trois-six" 941

Z

Zaharoff, Basil
557; at Ostend

Zanni
708; Theign's half-invented "local operative" in Venice

Zarzuela
81; Webb Traverse's colt

Zengg
697; "headquarters of the [...] New Uskok movement;

Zero
"a sub-zero-degrees version of Hell," 41; 185; 243; converging to, 589; 592; 594; 713;

Zeta-function problem
Also known as the Riemann hypothesis.
Riemann, 496; 498; 594;

Zetamaniacs
589; 619;

Zhukovsky's Transformation
603;

Zilberfeld, Yitzhak
165; Zionist agent in Eastern Africa with his theory about Anti-Semitism

Zion
131; 165;

Zip
18; member of the Bindlestiffs of the Blue A.C.

Zodiac
406;

Zöllner, K. F.
591;

Zoltan
463; vampirish, from Hungary, "drives a Werner"

Zombini, Bria
351; Luca's and Erlys's daughter; 574; back in Venice, 583;

Zombini, Cici
352; Luca's and Erlys's son and "coin specialist"; elephant trick, 569;

Zombini, Concetta
352; Luca's and Erlys's baby daughter;

Zombini, Dominic
352; Luca's and Erlys's son;

Zombini, Elijah
570; Negro ancestor and master chef

Zombini, Luca "The Mysterious"

For what it's worth, it seems The Great Zombini and Viv was a doll set sold exclusively at Tower Records. Some text (from this ebay auction page) that was apparently part of the dolls' snazzy coffin-shaped packaging reads as follows:

The Great Zombini has a trick for you all,

His lovely assistant split by the blade of his saw.

The crowd had gathered to see a trick,

But Zombini opted to make them sick.

As his assistant lies trapped in a box, afraid,

He severs her body with the cut of his blade.

28; ran away with Merle Rideout's wife, Erlys; 57; 67; in Venice with entire family, 568;

Zombini, Lucia
352; Luca's and Erlys's daughter;

Zombini, Niccolo
569; ancestor - 17th century Venetian apprenticed to mirror-makers

Zombini, Nunzi
352; Luca's and Erlys's son;

zone of dual nature
633; at Museum der Monstrositäten;

Zone of Emergency
125; 139;

Zoot, Dr.
402; and his time machine; 407

Zsuzsa
702; her salon in Vienna;