Glower from club user initially barred (5)

I believe the answer is:

ember

I'm a little stuck... Click here to teach me more about this clue!

'glower' is the definition.
(I've seen this before)

I cannot understand how the rest of the clue works.

(Other definitions for ember that I've seen before include "Material in dying fire" , "Glowing coal; type of goose" , "Glowing, smouldering piece of coal or wood" , "One smouldering" , "Glower" .)

I've seen this clue in The Telegraph and The Sun.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.