(Latin: prefix; to, toward, a direction toward, addition to, near, at; and changes to: ac-, af-, ag-, al-, an-, ap-, aq-, ar-, as-, at- when ad- is combined with certain words that begin with the letters c, f, g, l, n, p, q, r, s, and t)
The Latin element ad carries the idea of "in the direction of" and combines with many Latin words and roots to make common English words.
The form ad- appears in this form before a vowel and before the consonants d, h, j, m, and v. It is simplified to a- before sc, sp and st.
Before c, f, g, l, n, p, q, r, s, and t; ad- is changed to ac-, af-, ag-, al-, an-, ap-, aq-, ar-, as-, and at-.
In other words, the d of ad usually changes into the same letter as the first letter of the following root or word when it is a consonant: ad-fix becomes affix, and ad-sign becomes assign; therefore, making a double consonant.
Another example includes: attract as with ad-tract (drawn towards); so it has a double t. On the other hand when ad- precedes a vowel, as with adapt, it is simply ad-apt, with one d. For the same reason, there is only one d in adore and adumbrate, because ad- has combined with orare and umbra each of which starts with a vowel.
So, remember: since these Latin words begin with vowels and not consonants, the d of ad does not double as shown in the previous examples.
2. Etymology: from Old French fornication, from Late Latin fornicationem (fornicatio; from fornicari "to fornicate"; from Latin fornix, "brothel"; originally "arch, vaulted chamber"; from fornus "arched or domed shape".
Roman prostitutes commonly solicited customers from under the arches of certain buildings; therefore, fornication means, "intimate relations between an unmarried man and an unmarried woman"; extended in the Bible as adultery.
2. To put something forward; such as, a proposal.
3. To supply something or part of something; especially, money, before it is due.
4. To rise, or to make or help someone rise, in rank or position.
5. To make something happen earlier than originally expected.
6. Etymology: from Latin abante, "before" which was based on ab-, "from" and ante, "before".
2. A circumstance or factor that places a person in a favorable position in relation to another individual or to other people.
3. Etymology: from Old French avant, "before"; from Latin abante, "before".
2. The rate of change of an atmospheric property caused by the horizontal movement of air.
3. The horizontal movement of water, as in an ocean current.
This condition is found especially along a coastline where the temperature of land and the temperature of water significantly differ.
"The layer known as adventitia is a pliable sheet of tissue that covers, lines, or connects the organs or cells of animals or plants."
2. Appearing casually, or out of the normal or usual place; especially, in botany of roots, shoots, buds, etc. produced in unusual parts of the plant.
3. Not in the usual order or place.
4. Not natural or hereditary; such as, roots that form on stems, a growth of hair where it usually does not grow, or the growth of a plant in a foreign habitat.
2. A chance occurrence, an event or issue, an accident.
3. A hazardous or perilous enterprise or performance; a daring feat; hence, a prodigy, a marvel.
4. Any novel or unexpected event in which one shares; an exciting or remarkable incident befalling any one.
5. The encountering of risks or participation in novel and exciting events; adventurous activity, enterprise.
In summary: adverbs tell manner (how), time (when), place (where), degree (how much), and sometimes cause (why).
Adverbs of manner: "politely, carefully, not, equally, tenderly".
Adverbs of time: "now, then soon, later, early, often".
Adverbs of place: "here, there, near, forward, far."
Adverbs of degree: "very, so, much, too, extremely, rather."
Adverbs of cause: "why, therefore, hence".
2. Etymology: from Anglo-French adverser, from Old French adversier, from Latin adversarius, "opponent, rival"; literally, "turned toward one", from adversus, "turned against".