pattern - Find the secret word

Here is a list of words.

Mother
Clam
Game
Anagram
Immune
Maximum
Image

In each word, there is an indication on how to read a secret word.
But some words gave a false indication and should be ignored.
Can you find the secret word?

NOTE
If this proves to be harder than expected, some hints will be added after a while.

HINT

All these words have something obvious in common which act as an indicator of how to read the secret word.
Some of these words are slightly different in the way they give that hint and should be ignored.

You must find in what way the indications are telling you how to read the secret word.

Answer

The answer is

Magic

Explanation:

First letters of the words indicated by the position of the letter m in each word. Words with more than one m should be ignored.

Mother - 1 --> M
Clam - 4 --> A
Game - 3 --> G
Anagram 7 --> I
Immune (ignore, more than one M)
Maximum (ignore, more than one M)
Image 2 --> C