The word "siyara" means striped with silk.
Sunan Abi Dawud Book 34, Hadith 39
← Previous Hadith The Prophet of Allah (ﷺ) took silk and held it in his right hand, and took gold and held it in his left hand and said: both of these are prohibited to the males of my community.

Sunan Abi Dawud Book 34, Hadith 38 Next Hadith → We used to take it away (i.e. silk) from boys, and leave it for girls. Mis'ar said: I asked Amr ibn Dinar about it, but he did not know it.

Sunan Abi Dawud Book 34, Hadith 40