Named plazas are frequently used points of reference when directions are given. The large malls like Plaza las Americas will probably be known to you after your first explorations of the town, but smaller ones may not be noted on Google maps or elsewhere. Some are single buildings, not what you'd think of as a plaza space. So, here is a start on a guide to Cancun plazas large and small.
Mercados 23 and 28 are named for their supermanzanas.
I have noted the Supermanzana for each plaza, although it takes a while for those to become meaningful to visitors. Aside from Mercados 23 and 28, you may never be aware of which you're in. But they are a key part of Cancun addresses, and used daily by real estate agents, taxis and residents to indicate location, so it doesn't hurt to learn a few.
Plaza Bonita, SM 28
the northeast section of Mercado 28. Xel-ha is the road that rings Mercado 28, and Av Sunyaxchen brings you into it near Plaza Bonita, as does Av Tankah. Has businesses similar to the rest of the marketplace as well as a very recommendable dentist, Dra Rosario Sauza Aguilera (Whatsapp 998 7349313), and other offices.
Plaza Comalcalco, SM 97
out Av Andrés Quintana Roo past City Club, just before a Wal-Mart known as the Zona Industrial location. Home to a medical laboratory and a flower wholesaler.
Plaza Las Fuentes, SM 43
at Av La Luna and De Las Palmas, site of a couple of bar-restaurants and a small gym.
Plaza Galerias, SM 2
east side of Av Tulum, about halfway between Av Chichen-Itza and Av Uxmal (ADO bus station)
Plaza Hollywood, SM 35
between Av Coba & Av Xcaret on the east side of Palenque, very close to the first Wal-Mart (which I believe is still open 24 hours).
Starbucks, several banks, and the largest location of La Europea wine and liquor store.
Plaza Monarca, SM 35
between Av Coba & Av Xcaret, west of Yaxchilan, east of Av Tankah/Labna. Thus, first block west of big IMSS complex
Plaza Nayandei, SM 4
East side of Bonampak about mid way between Kukulkán (road to Hotel Zone) and Sayíl (Plaza de Toros). Home to Office Depot, Taste of India, Mr. Pampas and one location of La Casa de los Abuelos.
Plaza las Palmas, SM 36
north side of Av Xcaret, east side of Av La Costa. This means, opposite Estadio Andres Quintana Roo to the north.
Plaza Solare, SM 6
east side of Bonampak, south side of Sayil, which means across from Plaza de Toros. Several restaurants.
Plaza Sunyaxchen, SM 24
on the stretch of Av Sunyaxchen between Mercado 28 on the west and Av Yaxchilan on the east. Two restaurants at plaza level, Rooster (with some sidewalk tables) and Patravali, with an unnamed salon in-between.
Plaza las Americas, SM 7
The main shopping complex outside the Hotel Zone (with Puerto Cancun being part of the Hotel Zone), between Av Tulum & Av Bonampak, south of Av Sayil (Plaza de Toros) and running all the way to Av Nichupte
Sears, Liverpool, Cinepolis, Chedraui, food court, Radio Shack, Sanborn's, many restaurants and boutiques.
Plaza de Toros, SM 4A
east side of Bonampak, north side of Sayil, placing it diagonally NE of Plaza las Americas.
Plaza Tucanes, SM 45
east side of Kohunlich, about five short blocks south of Av Andrés Quintana Roo. Has several small restaurants and stores.
Las Plazas Outlet, SM 39
A major shopping complex on the north side of Av Andrés Quintana Roo. (Note that Av Xcaret becomes Av AQR once you cross Kabah heading west, and this plaza begins shortly after. It extends to Av Tikal, or, coming from the south, Av. Kohunlich.) Home to City Club, a Cinepolis, and large mall of boutiques and small restaurants. To the east of this plaza, you find a Soriana and north of it, on Kabah, is Home Depot.
La Gran Plaza, SM 51
may be a little further west than many tourists go; south side of Nichupte down to Av Technologico, east side of Calle Tepich. More broadly, found in the stretch west of Av La Luna and east of Av Kinic. Another large shopping center including a Wal-Mart and a cinema complex. Its parking lot is one of the locations for monthly recycling collection.