Sheet, Sheetlet Definition

I struggled witht he topic subject, so if anyone has a better one after reading the question, feel free to suggest.

My question is what to call the format that most US stamps are now issued in. Commemoratives and other special stamps come as "sheets" of 20 self adhesives with a selvage around the stamps. The selvage may or may not have decorative elements.

I don't think they are called sheets. I have been calling them sheetlets. They are definitely not souvenir sheets. ( Are they?)

I also don't think they are panes. I have looked at the Linn's definitions and just have not been satisfied with the information.

Does anyone have any insight?

There are probably as many definitions as there are collectors. In my mind, sheets used to be the old gummed stamps that had 50 or 100 stamps per "pane"; when they cut them down to 20 stamps, I've referred to them as "sheetlets".

However, if you look at the USA Philatelic Magazine issued by the US Postal Service for ordering commemorative stamps, the sheetlets of 20 are referred to as "panes", or more precisely "Pane of 20 with Plate Number and Header."

However, in the case of the Hollywood Stars (i.e. Gregory Peck, Katharine Hepburn, etc.) where there is a non-stamp section of the pane with their image and write-up, the description changes to read "Pane of 20 with Plate Number and Selvage."

From "Ask Phil"

Sheetlet: 1: a small pane of stamps; less than what is normally considered by normal
standards as a usual pane; in the U.S., a normal pane consists of 20 or 50 stamps,
while a sheetlet would be sheets of less than that quantity. 2: Michel 2001 Catalogue
considers items with the same four stamps as a sheetlet provided it does not also
appear at the same time as a block; items with five to ten of the same stamp are
sheetlets; see Blocks, Combination sheetlets, Combination sheets.
Sheet margin: the portion of unprinted paper that surrounds a stamp or a pane of
stamps.
Sheet numbers: consecutive numbers placed on sheets by an automatic numbering
machine to keep an accurate count of the number printed.
Sheet Stamp: stamp produced in sheet format, vs a stamp made in a coil or booklet
pane format.
Sheet Waste: stamps with incorrect perforations or misaligned colors, etc., remnants
of some rotary press sheet stamps that were perforated gauge 11, creating rare stamps.

Souvenir sheet (SS): 1: sheet of a stamp or stamps, surrounded with a paper margin
issued for a specific event or purpose. 2: first U.S. SS is the White Plains pane of 25
stamps for an international stamp exhibition, held Oct. 16-23, 1926. 3: gedenkblock
(Ger.); bloc feuillet (Fr.); foglietto (It.); hoja blocque (Sp.).