Word for when we accidentally invert the syllabic utterances of words?

Today, during a conversation, one of my friends accidentally inverted the syllables of the word "bookmarks" as "markbooks." Then I immediately thought about describing such a mistake in speaking.

I asked my elder brother, who suggested I regard it as stuttering. But sadly, this word doesn't fit well for what I am asking over here, since stuttering denotes the repetition of sounds pertaining to just initial consonants:

verb 1. talk with continued involuntary repetition of sounds, especially initial consonants.

See the following image about stuttering:

In the image above, there's talk of the word "soda", which is written as s-s-s-s-soda to express stuttering.

There might be a word describing the inversion of syllabic utterance of words.

"He said 'markbooks' rather than saying 'bookmarks' because of _____ [in place of the word 'stuttering']"

The word I am asking for here can be a verb (an act of doing what I described here), or noun or noun-phrase to describe such an accidental act.

My question is different from "Is there a term for switching syllables of words?". In that post, the OP's primary question is about the exchange of two different syllables belonging to two different words; as his first example tells "trace" and "race", which are different and both having their own distinct syllables. Whereas my question is about the exchange of syllables within the same word and without dropping any letter(s) of words e.g.:

bookmarks > markbooks

clockwise > wiseclock

Textbook > booktext

Any kind of switch in order, whether sounds, syllables, or words, is called:

metathesis

(/mɪˈtæθɪsɪs/ with accent on the second syllable).

Examples are:

• common pronunciation of 'comfortable' as 'comfterble' /ˈkʌmftərbəl/
• 'peckerwood' for 'woodpecker'

A spoonerism is a kind of metathesis. For example, "A well-boiled icicle" ("well-oiled bicycle").

In rhetoric, changing out of the usual word order is also called

hyperbaton

(having numerous rhetorical synonyms like anastrophe or synchysis).

Of course 'metathesis' (not to be confused with 'metastasis' a spread of cancer to a secondary site), is a bit technical sounding. A more natural sounding alternative might simply be

switch

or

transposition

or as you mentioned

inversion.

These are all mostly intentional (except for a Spoonerism). If what is happening is an actual mistake, then it might additionally be called euphemistically a

solecism.

The most common term I've heard for this is a "Spoonerism". It's a reference to William Archibald Spooner who was known for making these kinds of utterances unintentionally.