"He is my boss."
Translation:Он - мой начальник.
Am I correct in thinking that job/role nouns that end in -ник are for men only?
What is the word for a female boss?
However, it's possible to use masculine words denoting professions to refer to women. So, both «Она́ моя́ нача́льница» and «Она́ мой нача́льник» are correct.
Thanks. Are there any connotations attached to choosing one form rather than the other?
In this particular case the difference is negligible.
However, for many professions, no neutral feminine word is readily available, so you have to use a masculine word. (There're attempts to change this, for example, authors of this VK.com group keep suggesting feminine forms for many words: https://vk.com/f_fem — but these are not readily accepted as correct by many speakers.)
Fascinating. The trend in English is in the opposite direction. For example, some actresses demand to be referred to as "actors", because they perceive the grammatical flagging of their gender to be patronising.
"Хозяин" = "owner", "master", it works with property, things, pets/animals and slaves.
I've never heard «менеджер» used this way. I think many (most?) people who are called менеджер in Russian are not actually anyone's bosses. There's even a joke that cleaners are nowadays called «менеджер по клинингу» because it sounds cool.