'-m-n — to be firm, steady, trustworthy
א.מ.ן (aman) is the root of amen, emunah (faith), ne'eman (trustworthy) and the modern Hebrew for a sports coach. The core sense is firmness, not belief.
The word family
Every word below is built on א.מ.ן. Same three letters, different vowels and prefixes.
Closer to steadfastness than to belief in a proposition.
One who makes you steady through repetition.
In the text
וְהֶאֱמִן בַּיהוָה
v'he'emin ba-Adonai
And he trusted in the LORD.
What I tell students about this root
Saying amen is not saying "I hope so". You are saying the thing just spoken is solid, it will bear weight. Once you see the root as firmness, emunah stops meaning belief-without-evidence and starts meaning the reliability of a load-bearing wall — which is also why the same letters end up producing the word for a coach.