These three letters carry the idea of rising, swelling up, and what that does to a person. Water rises and floods; a person who rises in their own eyes is proud, for better or worse. So the family runs from the physical surge of a tide to the feeling of pride, and on to greatness and even genius. The same upward motion can lift you or tip into arrogance. Every word below 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 two verbs split the root's literal and figurative sides. The plain pa'al לִגְאוֹת is physical: water rising, a tide swelling. The reflexive hitpa'el לְהִתְגָּאוֹת turns it inward: to lift oneself up in feeling, i.e. to be proud. Pride is, quite literally, rising in one's own eyes.
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.