How rush-hour subway trains are packed (7)
I believe the answer is:
densely
(Other definitions for densely that I've seen before include "Thickly" , "in a crowd" , "measure of concentration" , "In a thick manner" .)
I've seen this clue in The Washington Post.
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.