اطمأُطُمٌ and أُطْمٌ, (S, K,) like أُجُمٌ and أُجْمٌ, (S, and Mgh in art. اجم) A fortress: or, as some say, any lofty building: (Mgh:) or a [building such as is termed] قَصْر [q. v.]: (IAar, K:) and any fortress built of stones: and any square, roofed, house: (K:) pl. (of pauc., TA) آطَامٌ (S, Mgh. K) and (of mult., TA) أُطُومٌ: (K:) آطَامٌ signifies fortresses of the people of El-Medeeneh: and one of these is termed ↓ أَطَمَةٌ: (S:) or this signifies [simply] a fortress; and its pl. is آطَامٌ (TA.) أَطَمَةٌ: see above.آطَامٌ مُؤَطَّمَةٌ Lofty [fortresses, &c.]: (A, TA:) [or it may signify fortresses, &c., disposed in order, or grouped together; for it is said to be] a phrase like أَبْوَابٌ مُبَوَّبَةٌ, (O, TA,) or like أَجْنَادٌ مُجَنَّدَةٌ. (K.)