Structured Word Inquiry of ‘Enthusiasm’

What is the base morpheme of the word enthusiasm? To begin the structured word inquiry, I looked up enthusiasm on Etymonline and Wiktionary. The word enthusiasm comes from Ancient Greek enthousiasmós, which comes from en “in” + theós “god” + ousía “essence.”

I could initially break the word down into these morphemes:

The <en> is prefix that denotes “in.” The <asm> is a suffix that denotes an action, state, or result and is also found in the words orgasm, phantasm, pleonasm, protoplasm, and sarcasm. I can also remove the -asm and add the suffix -ast, which is an agent suffix.

I thus questioned whether the base of enthusiasm is <Thusi> or if the <Thusi> is further analyzable.

To investigate <Thusi> further, I first reviewed the etymology, noting that this part of the word comes from Ancient Greek theós “god” + ousía “essence.”

The Ancient Greek theós gives English the bound base <The> with a pronounced final <e> as in atheist, theocracy, theogony, theology, theonym, theophany.

I also discovered that the Ancient Greek ousía “essence” gives English the word Parousia:

I needed to investigate that <Ousia> further, but first I needed to acknowledge that I had previously identified an <Ousi> base that denotes “essence, being” from Ancient Greek ousíā as in words such as homoiousian, homoiousia, homoiousians, heteroousian, homoousian, monoousian, homoiousianism.

This <Ousi> comes from Ancient Greek ṓn, oûsă, ón “being,” the present participle of eimĭ́ “to be” + -ĭ́ā “abstract noun suffix.” In Modern English, the -ia is the connecting vowel -i- + the suffix -a, so I knew that I needed to reanalyze <Ousi> as being <Ous + i> with the bound Ous base denoting “essence, being.”

The question at this point was (1) whether <Thusi> is a base that comes from theós + ousía or (2) if <Thusi> is further analyzable.

I had already identified that the <i> that follows the <Ous> in words like homoiousian, monoousian, and Parousia is a connecting vowel. I thus considered whether the <i> in <Thusi> is also a connecting vowel. Connecting vowels do not cause doubling but do replace a replaceable <e>, so I tentatively added a replaceable <e> to the new <Thuse> base to prevent doubling. If I found any words in which the <s> in a potential <Thus> does double, I would remove the <e> from the proposed <Thuse> base.

English also has the word enthuse, which is a backformation from enthusiasm but which adds evidence for a <Thuse> base:

The question was still whether <Thuse> is a base or further analyzable. The hypothesized <Thuse> comes from theós + ousía, so, to be further analyzable, English would have to have <Th> and <Use> bases from theós and ousía. Does English have any other words with a <Th> (not followed by <e>) base denoting “god, deity” or any other words with a <Use> base denoting “essence, being”? Or is <Thuse> unanalyzable?

All known examples from theós (atheist, theology, theism, theocracy) preserve the <The> base with final <e>. No known English words have a <Use> base denoting “essence, being”.

Thus, the base is <Thuse> denoting “fervor, inner inspiration, or animated feeling originally associated with divine possession or spirited essence.”

I thus concluded my structured word inquiry of the word enthusiasm with the bound base <Thuse>: