It may be part of a word, Stephen, and thank you for responding on the thread, as I know you have knowledge in this area.
I am not as familiar with Greek abbreviations as I am with Latin. I only know some of the most common ones (mostly the ones that carried over into Latin).
In Latin, an abbreviation doesn't always mean a word. For example, the m abbreviation in languages that use the Latin alphabet represents the common abbreviation "-ris" (and its homonyms), which is not a word, but a syllable. It is comprised of the letters "r" and the loop+descender that usually represents "is".
So maybe "atto" is a syllable rather than a word? The ligature for gamma-gamma (the square form, not the cursive form) is also one of the staircasy ones and somewhat resembles the way some of the VMS gallows chars are sometimes combined in the main text, by placing the second one slightly higher and to the right of the first.
As mentioned, the abbreviations that look like staircases I have seen mostly in Greek palaeography charts. They stood out to me because most Latin and Greek abbreviations are rounded in the cursive style and these were different. I've never seen them in a Latin manuscript and I haven't gone through enough Greek manuscripts yet to have seen all the abbreviations (mostly I've been looking at Greek mss. about plants and medicine).
I'll try to find the examples I saw. It was a few years ago so I have to hunt them up again.
Other Possible Shapemates
The only other place I've seen these staircased shapes (some portions are rectangular, some like triangles), is in Mandaic alphabets, where some letters are comprised of angles and partial rectangles, somewhat similar to the shape in the VMS. Mandaic evolved from Armenian or Parthian.
For example, in Mandaic, which has a syllabic alphabet, you start with a simple staircased shape and then you can add a 1) triangle or 2) short stem to the left side to represent the vowels "a" or "i". With consonant and vowel combined, it looks somewhat like the VMS rare shape. The letter + vowel that is most similar to the VMS glyph represents "t" or theta in the Mandaic alphabet, "m" is also similar, but it depends on the scribe. Some of the other letters follow the same concept but are not as similar.
But... the Mandaic syllables only look similar in their square form. The cursive form is less like the VMS. It has rounded connectors, which makes the triangles and rectangles look softer and more like western letters. So... it's not a super-strong resemblance except in certain instances, but I mention it for the record.
Even though the resemblance to Mandaic is not super-strong, I looked into it because the script was traditionally added to talismanic objects (like demon bowls and healing bowls). If the VMS has any connection at all to kabbalah or other Semitic magical scripts, then these talismanic objects may be of interest.
I am not as familiar with Greek abbreviations as I am with Latin. I only know some of the most common ones (mostly the ones that carried over into Latin).
In Latin, an abbreviation doesn't always mean a word. For example, the m abbreviation in languages that use the Latin alphabet represents the common abbreviation "-ris" (and its homonyms), which is not a word, but a syllable. It is comprised of the letters "r" and the loop+descender that usually represents "is".
So maybe "atto" is a syllable rather than a word? The ligature for gamma-gamma (the square form, not the cursive form) is also one of the staircasy ones and somewhat resembles the way some of the VMS gallows chars are sometimes combined in the main text, by placing the second one slightly higher and to the right of the first.
As mentioned, the abbreviations that look like staircases I have seen mostly in Greek palaeography charts. They stood out to me because most Latin and Greek abbreviations are rounded in the cursive style and these were different. I've never seen them in a Latin manuscript and I haven't gone through enough Greek manuscripts yet to have seen all the abbreviations (mostly I've been looking at Greek mss. about plants and medicine).
I'll try to find the examples I saw. It was a few years ago so I have to hunt them up again.
Other Possible Shapemates
The only other place I've seen these staircased shapes (some portions are rectangular, some like triangles), is in Mandaic alphabets, where some letters are comprised of angles and partial rectangles, somewhat similar to the shape in the VMS. Mandaic evolved from Armenian or Parthian.
For example, in Mandaic, which has a syllabic alphabet, you start with a simple staircased shape and then you can add a 1) triangle or 2) short stem to the left side to represent the vowels "a" or "i". With consonant and vowel combined, it looks somewhat like the VMS rare shape. The letter + vowel that is most similar to the VMS glyph represents "t" or theta in the Mandaic alphabet, "m" is also similar, but it depends on the scribe. Some of the other letters follow the same concept but are not as similar.
But... the Mandaic syllables only look similar in their square form. The cursive form is less like the VMS. It has rounded connectors, which makes the triangles and rectangles look softer and more like western letters. So... it's not a super-strong resemblance except in certain instances, but I mention it for the record.
Even though the resemblance to Mandaic is not super-strong, I looked into it because the script was traditionally added to talismanic objects (like demon bowls and healing bowls). If the VMS has any connection at all to kabbalah or other Semitic magical scripts, then these talismanic objects may be of interest.