The Arabic word nutfatin amshaajin means mingled liquids. According to some commentators of the Qur’aan, mingled liquids refers to the male or female agents or liquids. After mixture of male and female gamete, the zygote still remains nutfah. Mingled liquids can also refer to spermatic fluid that is formed of various secretions that come from various glands.
Therefore nutfatin amsaj, i.e. a minute quantity of mingled fluids refers to the male and female gametes (germinal fluids or cells) and part of the surrounding fluids.