Ph.D At mid 40s - US - Lecturer A quick question. If someone start his/her Ph.D at the age of 44 and finish it by 50, what are the chances of joining academic world as a tenured lecturer in US
(copying from my own comments above with some tweaking)

Lecturer is primarily a teaching position and is not tenure track.  Tenure track comes with research responsibilities.  Entry level on tenure track is assistant professor. If you publish and do well, you might be promoted to associate professor and gain tenure after perhaps 3 to 7 years. It's very unlikely you would "join" with tenure.

If your objective is simply that you'd like to teach at a university because you think it would be rewarding (it is) and you're not so interested in research, you want to be a lecturer, even though it will never get you tenure. And you may be able to do that now with only a master's. These positions often require PhD but not always. It depends on how the search committee decides to write their ad.  You might also consider teaching as an affiliate lecturer.  These are part-time appointments that don't require a competitive search, usually only a faculty vote.