Lord of the Left

Question: What are some of Huitzilopochtli's other names/titles?

The Aztec god of the sun isn't an Odin, saddled with a thousand titles and epithets, but his people nevertheless knew him by a few different names. His most common name, Huitzilopochtli, is usually translated as "hummingbird on the left-hand side", from huitzilin, meaning hummingbird, and opochtli, meaning left-hand. An alternative translation is "hummingbird of the south", which might refer to his place as the one of the four Tezcatlipocas who presides over that quarter of the world.

Other names include:

Inaquizcaotl - While this is given as a name of Huitzilopochtli in a few old Spanish sources, its etymology is unknown and no one is quite sure what it's supposed to mean. "Quiz" usually means some form of "outward", as in coming out, going out or emerging; "caotl" isn't a common word in Nahuatl and may be a mistransliteration of the more common "coatl", meaning snake. That would give us a tenuous translation of "the arriving serpent" or "emerging serpent", maybe referring to his use of Xiuhcoatl as a weapon.
Mexi - Although this one is debated, at least a few sources relate that Huitzilopochtli gave his name as Mexi to his people when he first led them from the wilderness. The name of their people, Mexica, would therefore literally mean children or followers of Mexi, and the name of the country, Mexico, would mean place or city of Mexi. Mexi is most likely a shortened form of mexitli, which refers to a hare, although why he would have that title we don't know. It may refer to a myth that hasn't survived to the modern day.
Paynal/Paynalton - This is actually technically the name of Huitzilopochtli's earthly avatar, who arrives on earth to interact with mortals so that the god's full glory doesn't blast unsuspecting humans. A neat example of a god in mythology actually using the Avatar Birthright.
Teoyaotlatohuehuitzilopochtli - The most formal of the sun god's titles, this mess means "Huitzilopochtli the Divine Lord of Warfare". Just think, his normal five-syllable name is the abbreviated short form.
Tetzahuitl - This title means "terror" and is generally used to refer to him when he's busting it up on the battlefield
Tetzateotl - Similarly, "terrifying divinity", making it clear that we're talking about a god. Who is also scary as shit.
Tlaxotecatl - One of the most famous of Huitzilopochtli's epithets, the "divine hurler" or "divine thrower", referring to his insane throwing prowess that allowed him to hurl his defeated siblings into the sky to become stars and hurl the fire of the sun from Xiuhtecuhtli.
Xoxohuic Tlacochtli - Literally, "the blue javelin", which probably refers to both the god's brilliant blue coloring as a hummingbird and his association with airborne weapons and attacks.
Yaotecuhtli - Literally "lord of war". Because that's what he does.
Yaotzin - This one just means "enemy" and is another war epithet of Huitzilopochtli's, referring to his tendency to trash opposing armies. It's also occasionally used to refer to Tezcatlipoca, although the inscrutable jaguar-god is as often his own family's enemy as anyone else's.

There are probably a few more floating around - shout them out if you got them! - but those are the ones I know off the top of my head. Ain't nobody got as many syllables in their titles as the Teotl.