What is the ‘a-’ in ‘alive’?

What is the ‘a-’ in ‘alive’?

‘It’s alive!’ we popularly exclaim of the
vivification of Frankenstein’s monster. But once animated, the creature doesn’t have alife or isn’t aliving . Dr Frankenstein gave the creature
life , we would say. He made it living . The -live , and its connection to life and to live , is clear, so what is that a- doing in alive ?
The little letter ‘a’ can seem unassuming, but it does some heavy lifting. It leads our alphabet, of course, and, on its own as an article , it’s one of the most frequently used words in the entire language. As we see in the word alive, ‘a’ also does some serious work as a prefix. The Oxford English Dictionary enters five distinct senses of
prefixal a- , and that’s not counting the Greek-derived a- (or an- ), meaning ‘not’ or ‘without’ and seen in such words as apathetic or
apolitical .
Things quickly get messy, though, with initial a- , so let’s ease ourselves in, one a- at a time. We’ll start with alive.
The a- is afoot
In its core sense of ‘living’, the adjective alive has had a very long life. It’s recorded in Old English, but back then alive didn’t look alive, as it were. It was on life . This life is the dative case of the Old English root for life, lif . The familiar but multifunctional preposition on here has the sense of ‘in’ . That makes on life an
adverbial phrase with the force of ‘in life’, which we eventually came to treat as an adjective. This past likely explains why alive is predicative today, i.e., it comes after a verb. We say the dog is alive , never the alive dog .
So, the a- in alive is, essentially, on . And because on in on life comes in an unstressed position, its ‘n’ sound fell off and the remaining value, rendered with letter ‘a’, was smushed together with life , yielding alive . (The process for this was very slow, of course.) The original phrase on life did linger into the 19th century (though in later use it was a deliberate archaism), as the OED finds, while the prevailing adjective form, alive , is recorded by Middle English.
In Old English, a could function on its own as a reduced form of on or act as a prefix indicating onward movement. It survives in a host of common words besides alive . Asleep, above,
abroad , afloat, ahead , aloud , among, ashore ,
aside , and away: the a- in all of these go back to on in one way or another . About is a fascinating specimen, as it is a jumble of three prepositions if we dig down deep enough: on ,
by, and out .
Awaken is interesting, too. Its oldest form may be onwæcnan , reminding us that an adverbial
on- , here squished to a- , once prefixed lost, Tolkienesque verbs like ongin (begin), onseek (require), onstell (establish), and onwald (conquer). Again, the etymologies can be very convoluted, but underlying these instances of
a- is the preposition on .
A -’s aplenty
Once you notice these a- ’s, you start seeing them all over the language. But be aware : they are not all akin to each other, and other ones
arise. Aware , for example, begins as gewær in Old English. Its ge- is an old prefix that could express completeness; it was later rendered as
y- as in yclept , or ‘named’. Alike shows it, too, as does afford , whose origin we might break down as y-forth .
Meanwhile, the a- in akin starts as of. The word was originally the phrase of kin. And anew? That’s of new . Just like the Old English on , we whittled of down to a in earlier days – and in contemporary ones, too, lotsa times. (See what we did there?) Also like on , of- was once a productive prefix, seen in the Middle Earth-y likes of ofhold (detain) or ofthink (be displeasing).
As for arise, the a- adds intensity, often implying some kind of motion onward or away from a position, the OED explains. The a- is from another obsolete prefix rooted in ancient Germanic: or- , which the OED explains as primarily meaning ‘out’.There’s really only one familiar word holding onto or- as such, and that’s ordeal . Found in Old English, ordeal first named a kind of trial of pain or danger, such an
ordeal by fire, survival of which was taken as proof of innocence. The prefix or- , alas, did not endure its ordeal by time . (That a- , in alas , is interjectional (i.e. Ah! ): the word comes from the French a, las! Las means ‘miserable’, from the Latin root that gives us lassitude .)
Affright and allay accompany arise here, as does accurse , which survives in the adjective
accursed. The double consonants in these words appear to be influenced by words like
accompany , featuring the Latin ad- (meaning ‘to’), whose ‘d’ assimilated the initial consonant of its base.
At this point, maybe you’re a-tired of all these
a- ’s and find them all a bit a-muddled . This folksy-sounding a- , found in southern US and British regional dialects, is related to that
completive y- we saw in aware . It usually attaches itself to the past participle of verbs (which typically end in -ed ).
Another a-, particularly noted in the grammar of Appalachian English and often called a-prefixing , likes to head present participles (which end in -ing ). A-hunting we will go , so sings the old folk song. Where does this a- come from? The answer might be in the word that started this all: alive. This a- appears to go back to on , expressing a kind of activity that is
ongoing – a rare everyday word which displays that adverbial on- prefix we touched upon earlier.
We’d be remiss to miss a- or an- , a Greek-derived prefix meaning ‘not’ or ‘without’. Something atypical is ‘not typical’. Something
asexual is ‘without sexual feelings’. This prefix is negative or privative — it indicates absence, cancellation, removal, or the like. It also shows up in some surprising places: amethyst, for instance, comes from the Greek for ‘not drunken’, as the ancients believed the stone could ward off that dreaded hangover.
This was all much ado about a- . But no, the a- in ado is neither on or of , y- or or- . It’s at . Ado begins as at do, the preposition at here once functioning as to in infinitive verbs. Much ado about nothing ? Makes sense if we parse it as
much to do about nothing . But a- is definitely not nothing in the English language. Prefixal or initial a- , if no longer exactly productive in many of its historical forms, is still very much alive in our words. Sorting it all out, though, can feel positively monstrous.

Source
Oxford dict.