Careful: this root looks like its cousin ב־ח־ר (choosing) but it is a different family entirely. Here the idea is being first: the firstborn child, the ripe first fruit, the one who comes before the rest. From "first" grows "foremost", hence the senior official, and the act of putting one thing ahead of another, preference. The rare verb "to prefer" sits at the centre. Every word here is verified against pealim, niqqud included.
The same root runs through the verb system. Each binyan is a voice: it bends the one idea into active, passive, causative or reciprocal. Tap to hear.
The verb is rare and literary: in everyday Hebrew "to prefer" is usually לְהַעֲדִיף (root ע־ד־ף), not this one. The living core of ב־כ־ר is nominal, the firstborn and the senior, while the verb stays on the shelf. Not every root lives mainly through its verb.
Same root letters, different noun moulds (mishkalim). The mould tells you the function: who does it, the act of doing it, or the thing produced.
Strip the prefixes, suffixes and vowels. Three consonants remain, and the meaning lives there.