The Greek adjective austēros means austere, harsh, or exacting. Derived from a word meaning rough or astringent (like unripe fruit that makes the mouth pucker), it describes someone demanding and severe in their standards. In the New Testament it appears only in Jesus' parable of the minas in Luke 19.
Luke 19:21-22: the fearful servant accuses his master: 'you are an austere man.' The master does not deny it — 'You knew that I was austere, why then did you not...?' The servant's own words condemn his inaction. Theologically: fear of God's holiness should produce faithful stewardship, not paralysis. God's seriousness about accountability demands active investment of entrusted gifts.