They are LEGO bricks. There is no plural form of the word that is acceptable by the manufacturer and mostly AFOL’s try to follow this guideline. The LEGO Company is very keen about protecting the brand name.
Incidentally, there are LEGO Ambassadors who are liaisons between AFOL’s and The LEGO Company, often referred to as TLC. There are probably official statements that have been circulated about the use of the LEGO name.