La gira literally means "the tour" (like a music tour). However, in the context of this song and common Latin American slang, it takes on a more colloquial meaning of a "party spree" or a night out with friends that extends into multiple days.
In the lyrics, the singer laments, "Pero me perdí en la gira" (But I got lost in the party spree), indicating he was out partying and lost track of time, missing an opportunity to see the person he loves. This double meaning makes it an interesting and culturally relevant word.
"La Gira" is about drinking to numb heartbreak while stuck on the road. The singer compares himself to a sunken ship, unable to move past someone who left, and admits he goes out looking for her and settles for alcohol instead.
The chorus repeats the same cycle: he almost goes to find her, but gets lost in the tour instead, and thinks about giving away the bed where they used to be together, since someone else is in her place now but it feels empty and cold.
The bridge widens the picture, comparing the breakup to losing the sun and feeling like a coin with only one side. He is trying to move on with someone new, but keeps admitting he has not gotten over her.