bequest / will / commandment
Feminine noun. Plural: وَصَايَا (waṣāyā). Verb: أَوْصَى (Form IV, to bequeath/command). Also means divine commandment (as in God's waṣiyyah).
Islamic inheritance law balances fixed shares (farāʾiḍ) with the flexibility of the waṣiyyah - up to one-third of one's estate can be bequeathed freely.