firsthand
//ˈfɜːrstˌhænd//
Adjective
firsthandCanonical form
1
Obtained or experienced directly from the original source, without any intermediary.
I have firsthand knowledge of the situation because I was there.
Antonym
Adverb
firsthandCanonical form
1
In a direct manner; from the original source without an intermediary.
I learned about the company's culture firsthand by working there for a month.