'Tight' is used in the context of popular music (rock, jazz, pop, etc) to describe a solid 'groove', i.e., a song that has a good 'feel' and makes one want to dance. Can also refer to a band that has solid timing.
"Dude, did you hear that Steely Dan song, 'Do It Again'? It's tight as hell!"
by Rikki Number November 24, 2009