Valmiki Ramayana Yuddha Kanda Sarga 21 Shloka 6

दीर्घम् long, युगसङ्काशम् like the union of Yuga, संयुगे in war, शत्रूणाम् to the enemies, शोकवर्थनम् that which brings grief, सुहृदाम् to friends, नन्दनम् delightful, सागरान्तव्यपाश्रयम् like the earth bound by the ocean on all sides.

The shoulders were long like the union of Yugas, which brought grief to the enemies in war and delight to the friends, and like the earth bound by the ocean on all sides.