Pronunciation: [mˈə͡ʊst bˈɒtəm sˈa͡ɪd ˈʌp] (IPA) 
The correct spelling of the phrase "most bottom side up" is /moʊst ˈbɑtəm ˈsaɪd ʌp/. The word "most" is spelled with an "o" and "s" before "t." "Bottom" is spelled with "b," "o," "t," and "m." "Side" is spelled with "s," "i," "d," and "e." And "up" is spelled with "u" and "p." The phrase means to have the underside facing up, with the lowest point or part at the top.
There is no standard dictionary definition for the term "most bottom side up" as it appears to be a unique phrase that is not widely used or recognized in traditional dictionaries. However, we can analyze the phrase to derive a possible meaning.
The term "most bottom" implies a hierarchical structure or a vertical arrangement where multiple items are positioned one above the other. It suggests that there are several layers or levels, and "most bottom" refers to the lowest level or position within this arrangement. It could be interpreted as being closest to the ground or furthest from the top.
Additionally, the inclusion of the term "side up" can suggest a flipping or turning action in which an object is changed or inverted to its opposite orientation. This could imply that the initial placement or expected position of the object was reversed or altered.
Combining both phrases together, "most bottom side up" could colloquially be understood as the lowest layer or position of a structure that has been turned from its original orientation. This phrase could be used to describe an object or situation where the bottommost side or layer is unexpectedly facing upwards. However, it is important to note that without a more specific context or usage, the exact meaning may vary.
