protracted

Prolonged; continued.

Protracted meeting,a religious meeting continued for many successive days. [U. S.]

-- Pro·tract·ed·ly, adv. -- Pro·tract·ed·ness, n.

adjective

1. Of long duration: chronic, continuing, lingering, persistent, prolonged. See continue/stop/pause.
2. Extending tediously beyond a standard duration: dragging, drawn-out, lengthy, long¹, long-drawn-out, overlong, prolonged. See excite/bore/interest, long/short.

The adjective has one meaning:

Meaning #1: relatively long in duration; tediously protracted
  Synonyms: drawn-out, extended, lengthy, prolonged