Three letters, one of them a hollow vav, carry the heaviest idea in any language: death. The middle letter is a vowel-carrier, so this is a hollow (ע״ו) root: the vav hides and reappears as the form changes. From it you get the act of dying, the act of putting to death, the noun death itself, and the abstract state of being mortal. The whole family is small but old, and every form 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.
Two binyanim are lexicalized: the pa'al (the person dies) and the causative hif'il (someone causes the death). The hollow vav surfaces as the long u of lamut and as the i of lehamit. Everyday Hebrew also reaches for the separate root ה־ר־ג for "to kill" in the plain sense; lehamit is the more formal, root-internal causative.
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.