telephonic or telephone?
I also had a telephonic conversation regarding it with one of your employees.
I also had a telephone conversation regarding it with one of your employees.

Which one is correct telephonic or telephone? please explain

Question

telephonic or telephone?
I also had a telephonic conversation regarding it with one of your employees. 
I also had a telephone conversation regarding it with one of your employees.

Which one is correct telephonic or telephone? please explain

Answer

Both are correct.  Telephonic is an adjective, but in real life use “telephone” (although mainly a noun) gets used as an adjective.  In the US at least, it is far more common to hear “telephone conversation” and “telephonic conversation” (while correct) sounds a little bit formal.

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