They might be loaded with singles

I believe the answer is:

bases

(Other definitions for bases that I've seen before include "Fundaments" , "headquarters" , "Bottoms" , "On which things stand" , "Supporting layers" .)

I've seen this clue in The New York Times.

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.