针线 (needle and thread) is also a metonym for women's domestic handiwork:
做针线 means 'to sew/do needlework'. The phrase
临行密密缝 (mother sews tightly before son's journey) from Meng Jiao's 《
游子吟》 (Yóuzǐ Yín, 'Song of the Wanderer') made the
针线 image a classical symbol of maternal love.
