nect

The root nect comes from Latin nectere, meaning "to bind, tie, or fasten together," with the past participle nexus ("bound, tied"). Picture a Roman tying two ropes into a single knot, or fastening one object to another so they hold as one. That image of making a join is the heart of every nect/nex word.

The most everyday descendant is connect (con- "together" + nectere "tie") — literally "tie things together." When you connect two wires, two ideas, or two people, you are doing exactly what a Roman did with rope: binding separate things into one. From the verb comes the noun connection — the tie itself, or the relationship that the tie creates. Add the prefix inter- ("between") and you get interconnecting: things tied to each other across a network, each one bound to the next.

The second prefix is ad- ("to, onto"), which assimilates to an- before n, giving annex (ad + nectere = "tie onto"). To annex is to fasten something onto a larger thing — most often when a state ties a piece of foreign territory onto itself by force (annex a region), but also literally: an annex is a building tied onto a main building, and on paper an annex is a document tied onto a contract or report. The act of tying territory on is annexation.

Finally, the bare past participle nexus entered English almost unchanged. In Latin it meant a binding or even a legal bond of obligation; in English it became "a connection point" — the spot where many threads are tied together. A nexus of power is where lines of influence knot into one place.

The pattern is steady: nectere ties, the prefix says how or where the tie happens. con- ties things together, inter- ties them between each other, ad- ties one thing onto another, and the unprefixed nexus is simply the knot itself.