Contemporary: Past or Present?

In the multiple revisions of my thesis draft, I'm coming across some fairly common words in the English dictionary which have contradictory or odd alternate meanings.

For example, the word contemporary:
(1) living or occurring at the same time; dating from the same time
(2) belonging to or occurring in the present
So, if I say "contemporary historian", do I mean someone contemporary with my subjects or with me? That's a 150 year difference.

The word retire:
(1) leave one's job and cease to work, typically upon reaching the normal age for leaving employment
(2) withdraw to or from a particular place; to go to bed
So, if I say "Everyone retired early", do I mean that people left their jobs when they were only 50 years old or that everyone went to bed early? Strikingly different!

Context normally tells you everything, but not always. I guess that's what synonyms are for.

~ the well-spoken