Yes, though again, the language around registration gets really messy. Here's a great article (with a great title!) from the Journal of Singing by Christian T. Herbst "Registers—The Snake Pit of Voice Pedagogy": https://www.nats.org/_Library/JOS_On_Point/JOS-077-02-2020-1...

One relevant excerpt before the article goes into several pages discussing M11 vs M2:

> These four laryngeal mechanisms are typically termed as: vocal fry (M0, pulse register); chest voice (M1, modal register); falsetto (M2, head voice?); and whistle register (M3).

Another article by Dr. Ingo Titze (an icon in the field of voice science and basically the father of SOVTs) about the debated "mix" register, starts this way:

> One is called chest voice, full voice, or modal voice, which is described by a vibratory mechanism that some have labeled M1. Acoustically, harmonic energy above the fundamental dominates the sound spectrum in this register. The other anchor is called falsetto or light head voice, which is described by a vibratory mechanism labeled M2.

(from https://vocology.utah.edu/_resources/documents/mixed_registr...)