[PKop]

> Maybe he might have made it known to people

Yes, he coined the term rather than invent the technique

[adastra22]

He definitely did not name it. IRIS GL was termed “immediate mode” back in the 80’s.

[andypants]

He coined the term in the context of UI, by borrowing the existing term that was already used in graphics. Drawing that parallel was the point.

[pjmlp]

I won't be bothered to go hunting for digital copies of 1980's game development books, but I have my doubts on that.