the word = worthed
Spoonerism is the unintentional exchange of letters or syllables between two words or even within a word. The word derives from a 19th Century Clergyman. Also Metathesis is the reversal of letters within a word.
acronym
Those letters spell membrane.
Acronym
abbreviate example: U.S. = United States
There are no actual words spelled using sefsp. There is the slang term "fess."
The definition is "a group of letters used to represent a concept in a given langauge".
deoxyribonucleic acid
The letters 'nemvrametio' cannot be unscrambled to spell one word.They can spell the term "air movement."You can spell two nine lettered words using some of the letters. They are:ManometerNormative
In a mathematial equation the letters wither represent a variable or a constant.
the word = worthed
The term you are referring to is "anagram." An anagram is a word or phrase formed by rearranging the letters of a different word or phrase, using all the original letters exactly once. In this case, you are describing a specific type of anagram where shorter words can be formed using the letters of a longer word. An example of this would be the word "triangle," which can be rearranged to form the shorter words "rate," "ring," and "angle."
Zoomorphism
Its an abbriveation, if that's what you mean.
One anagram of those letters is "Arise, vanity" and a proper term is "Syria native."However,...it looks like the first "i" in the scramble was supposed to be an L : lsnteaiavyr = antislavery.
Two different words with the same letters, like vein and vane is called a homonym. Another homonym is formed by the words great and grate.