astir UK /əˈstɜː/US /əˈstɝ/ adjective2 •In motion; characterized by motion.Her book has perhaps been a good one; it has refreshed, refilled, rewarmed her heart; it has set her brain astir, furnished her mind with pictures. — 1849 •Out of bed; up and about.I had but a broken sleep the night before, in anticipation of the pleasure of a whole day with Em’ly. We were all astir betimes in the morning — 1849 formsmore astir · most astir