a part of a whole: a piece, share, region, or side, as set against the entirety
At its core this word names one bit of something larger, whatever the larger thing happens to be. That single idea stretches across a wide range in the New Testament. It can be a physical piece (a portion of a body, a fragment of fish, one of the four sections a garment was torn into), or the share that falls to a person (an inheritance handed over, or a lasting destiny like a place in the coming resurrection or in judgment).
The same word also maps space and groups. In the plural it points to a general area rather than an exact spot: the district around a town, the region a traveler passes through, the coastlands of a country. Applied to people it marks a side or faction, as when a crowd splits into those who agree and those who do not.
Finally it powers a set of stock phrases where it works like an adverb. Paired with small connecting words it yields senses such as in part, partially, one at a time, in detail, and in the matter of. In these uses the reader should not press the idea of a literal piece; the phrase simply signals that something is true only up to a point, or that a topic is being handled one segment at a time.
All of these hang together because each is still some slice of a bigger whole. The reader's task is to let the surrounding words decide which slice is in view, since English needs a different word for almost every one of them.