What is the morphology of the word adjutant? I read this word in an historical fiction novel set during World War II. I could see the possible ad- prefix and -ant suffix, which would leave a potential <Jute> base.
<ad + Jute + ant → adjutant>
To confirm my hypothesize morphemes, I first looked up adjutant in Wiktionary and Etymonline. I learned that an adjutant is an assistant, usually within the context of a lower-ranking military officer who helps superior officers.
As I suspected the initial <ad> is the ad- prefix denoting “to, toward, with regard to, in relation to.” English adjutant comes from Latin adiūtāre, which comes from ad- + -iūtāre, which comes from iuvāre + -tāre. Latin iuvāre means “aid, help, assist, give strength, support.” The base of adjutant is indeed <Jute>.
(As a side note, the vowel and consonant sounds now represented by the letters <i> and <j> were represented by only the letter <i> in Classical Latin. During the Middle Ages, a tailed form of <i> developed to distinguish the vowel from the consonant. This tailed <i> then developed into the letter <j>. The development of the letter <j> in English explains the spelling with the <i> in Latin iuvāre compared with the spelling with the letter <j> in English <Jute>.)
In addition to other words with the -ant suffix such as adjutantship and coadjutant, I also found the morphological relative adjutancy.
<ad + Jute + ant + ship → adjutantship>
<co + ad + Jute + ant → coadjutant>
<ad + Jute + ancy → adjutancy>
I then vaguely recalled a similar sounding word to adjutant that I had heard in relation to vaccines. I thus googled “vaccine adjutant,” which yielded the suggestion “vaccine adjuvant.” Adjuvant looks and sounds a lot like adjutant. Could the similarity be a coincidence? I thus looked up adjuvant in Wiktionary. Just like adjutant, adjuvant ultimately comes from Latin iuvāre. However, instead of coming through Latin adiūtāre, the <Juve> base comes directly from Latin iuvāre.
<ad + Juve + ant → adjuvant>
The base <Juve> also denotes “aid, help, assist, give strength, support.” The word adjuvant, which means “assistant, helper; helping, helpful, assisting,” also has the ad- prefix and -ant suffix. Morphological relatives include adjuvate and adjuvation.
<ad + Juve + ate → adjuvate>
<ad + Juve + ate + ion → adjuvation>
Because both words come from the same Latin root but entered English through different paths, adjutant and adjuvant are doublets.
I then decided to look for more relatives by investigating the Latin iuvāre more. Looking at the Wiktionary entry, I noticed the word iūcundus listed under derived terms, which looked to me like a possible ancestor of the word jocund. Latin iūcundus comes from the verb iuvāre and the suffix -cundus, which forms a present active participle denoting a tendency or inclination. The Latin -cundus developed into the -cund suffix in English as in fecund and rubicund.
<Fe + cund → fecund>
<Rube + i + cund → rubicund>
The word jocund descended from iūcundus and is therefore an etymological relative of adjutant and adjuvant. The base <Jo> denoting “please, benefit, help, support, assist” is a relative of <Jute> and <Juve>.
<Jo + cund → jocund>
I then finally searched for “iuvāre” on Etymonline to identify any other relatives. The first word to come up was aid. The semantic relationship to <Jute>, <Juve>, and <Jo> was clear. The etymology confirmed the etymological relationship.
The word aid comes from Middle English aide, eide, ayde, which comes from Old French eide, aide, from aidier, which comes from Latin adiūtō and adiūtāre, which come from adiuvāre, which comes from ad- + iuvāre. Like with the <Jute>, <Juve>, and <Jo> bound bases, the free base <Aid>v ultimately comes from Latin iuvāre but passed through Old French before coming into English.
By investigating the word adjutant, I not only discovered the bound base <Jute> but also the etymologically related bases <Juve>, <Jo>, and <Aid>. I also learned that adjutant and adjuvant are doublets.
