What is the morphology of the word egregious? At first glance, I see a probably -ous suffix on the end of the word. I also see a potential -i- connecting vowel, which would leave <egreg> or possible <egrege> with a replaceable <e>. (I will know if the replaceable <e> is required if a suffix follows the <g> rather than a connecting vowel, which replaces a replaceable <e> but does not cause doubling.) Another possibility is that the <i> is part of the base as in <egregi>. The initial <e> could also be a prefix, potentially a form of the ex- suffix, leaving a <greg> or <grege> base.
?<Egregi + ous → egregious>
?<Egreg(e) + i + ous → egregious>
?<e + Gregi + ous → egregious>
?<e + Greg(e) + i + ous → egregious>
To ascertain the morphemes in egregious, I look up the word in Etymonline and Wiktionary. The word now has a negative connotation, meaning “extremely bad,” but originally meant “distinguished, excellent, extraordinary.” Both sources indicate that the negative meaning likely arose from ironic or sarcastic use.
Looking at the history of the word, I see that English egregious Latin ēgregius from the phrase ex grege, which literally means “out of the flock.” Something that is egregious stands out from the group. The phrase ex grege consists of the Latin ex meaning “out of, outside of” and grege, which is the ablative singular of the word grex. The Latin grex is a noun meaning “group, flock.” The Latin verb gregāre meaning “gather, group” also comes from grex.
Wiktionary also notes that English egregious comes from Latin ēgregius plus the English suffix -ous as I hypothesized. The -ous suffix is an adjective suffix denoting “having, full of, having to do with, doing, inclined to.”
<Egregi + ous → egregious>
Based on the etymology, the base of egregious is <Greg> or <Grege>. Again, to determine if the replaceable <e> is required, I need to find a suffix that follows the <g>. The initial <e> is, as I hypothesized, the prefix e-, which is a reduced form of the Latin ex meaning “out of.” The remaining <i> is a connecting vowel that marks the <g> as spelling [d͡ʒ] rather than [g].
<e + Greg(e) + i + ous → egregious>
To determine if the base requires a replaceable <e>, I must now look for morphological relatives. I start by searching Etymonline for the term “grex,” which is the ultimate source of grege. Some relatives that I find include gregarious, aggregate, congregate, and segregate. I can immediately see that the base is the bound base <Grege> with a replaceable <e> because at least two suffixes following the <g> in just this handful of related words.
<Grege + ary + ous → gregarious>
<ag + Grege + ate → aggregate>
<con + Grege + ate → congregate>
<se + Grege + ate → segregate>
Thus, the morphology of egregious is <e + Grege + i + ous>.
