مهزول الفصيل
One whose young camel is lean.
In the conventional illustration, the young camel is lean because it has little access to its mother's milk, which is instead offered to guests. The listener infers frequent hospitality and ultimately generosity.
The inference runs through milk, guests, and service rather than moving directly from leanness to generosity. Its historical social setting helps explain why this is talwīḥ.