also: a small word that adds one more thing to what was just said, or leans on it for emphasis
This is one of the most common little words in the Hebrew Bible, and almost all of its uses grow out of a single idea: it takes something already in view and adds to it, points at it, or piles on top of it. At its plainest it means "also, too, as well," tacking another person or item onto a list ("she gave to her husband too"). The same adding move, pressed harder, becomes emphasis: it can spotlight a surprising or extreme case and shade into "even, indeed, in fact."
Hebrew also doubles the word to make a matched pair, one in front of each item, to say "both this and that" (or, with a negative, "neither this nor that"). And when it leans on a whole clause it can grant a point only to push past it, giving the sense "even though, although, yet."
Because English has no single particle that does all of this, translators reach for a different small word almost every time: also, too, even, indeed, yea, moreover, both, and. The thread running through them all is inclusion. The word never starts a new thought on its own; it always attaches to something already said and adds weight or another member to it.
The senses below are shades of that one idea, sorted by how the word is leaning in each place, not separate meanings. Which shade is in play is usually clear from the surrounding words, and the lines between "also," "even," and "indeed" are often soft.