adverbs - Can we say "Let's have a beer meanwhile they play tennis"?

I am a bit confused on how to use "meanwhile". I know you can use it as a connector. Meanwhile, I did not notice

I see dictionary.com says:

noun

1. meantime.

adverb

2. 
   

   in the intervening time; during the interval.

   
   


3. 
   

   at the same time: Meanwhile, the others were back home enjoying themselves.

   
   

I assume this is fine:

Let's have a beer. Meanwhile, they will be playing tennis

But I wonder, can you use it like this?

Let's have a beer meanwhile they play tennis

Answer

As the Lucian Sava pointed meanwhile is an adverb, here I want to point a difference in their usage and meaning.

According to Longman:

while : during the time that you are doing something, or something is happening.

meanwhile : at the same time as something else is happening.

As you see, meanwhile is used for two concurrent activities:

Let's have a beer. Meanwhile, they will be playing tennis.

Let's have a beer, and meanwhile they will be playing tennis.

In the sentence above both activities are important to be mentioned. You inform the hearer about two activities.

but while is used to focus on one activity that is happening during another activity.

Let's have a beer while they play tennis.

In the sentence above you mainly want to say "let's have a bear", but you also add that you do this while they play tennis.