Hello,
I learnt this word many years ago, “shadow”. I wonder if it has a meaning of being someone’s private teacher or special teacher for some people. :roll: Thanks.
F.F
Hi FangFang
The word shadow doesn’t specifically have that meaning. But you could say (my) shadow to refer to someone who is constantly present or nearby (for whatever reason).
Amy
Hi, Army
You mean the person who is always nearby to help others???
So can I say " You are my shadow?" :roll: 
Well… possibly. :lol:
But the sense of “nearby” would generally be physical rather than virtual. 
Your shadow isn’t necessarily a person. It might be your dog, for example.
If your shadow is a person, it doesn’t necessarily mean that the person is there to help you. It could be a spy, for example. :shock:
.
Some relevant meanings extracted from the American Heritage entry:
6b. A dominating presence or influence: spent years working in the shadow of the lab director.
11a. One, such as a detective or spy, that follows or trails another.
11b. A constant companion.
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