Silk Thread
noun
A silk thread is silk thread!
This is a jukugo word that uses the on'yomi readings of the kanji. You haven't learned these readings for 絹 and 糸 yet, so here's a mnemonic to help you:
Who only uses clothes made with silk thread? Ken's sheep (し)! Ken's sheep is very particular, and only wears clothes made from silk thread while it's waiting for its wool to grow back.
西陣の糸屋で絹糸を買ってきてちょうだい。
Please go buy silk thread at the Nishijin thread store.