The Tuesday immediately following the upcoming Tuesday; i.e., one week after the next occurring Tuesday (commonly understood as 'the Tuesday after next').
2.
General Englishinformalcolloquial
An ambiguous time expression used by some speakers to mean either 'one week after next Tuesday' or, alternatively, 'one week from now, on the day that is next Tuesday'; usage may vary by speaker or dialect.
Examples:
EN: I can get you a reservation a week from next Tuesday but you'll have to get a priority.
ES: Le puedo reservar dentro de una semana para el martes, pero tendrá que conseguir una prioridad.