ᴺS. !sûf n. “bosom” (Category: Breast of Woman)
A neologism for “bosom” coined by Ryszard Derdzinski in Parf Pith ’Wain (PPW) from the early 2000s, based on Q. súma “hollow cavity, bosom”. Unfortunately, in Sindarin phonology the final f [v] would vanish after ú, resulting in sú. I recommend using ᴺS. tith “breast, teat” instead, adopted from Early Noldorin (PE13/154).