Water off a duck's back
Umtea kollxar udok literally means “water on a large upside-down water pot. The equivalent English metaphor, “water off a duck’s back”, is therefore almost a literal translation of the Konkani one, except that as the water is poured from above, the umto kollso below is replaced by the duck. Yet the Konkani metaphor is perhaps more thorough in its representation in the sense that whereas at least some of the water poured over a duck may be retained by the duck’s feathers, the retention of water on an upside down pot is practically nil.
The Konkani phrase also has a wider scope and meaning. What the English expression “water off a duck’s back” is meant to convey is that criticisms of or warnings to a particular person have no effect on him or her. However “umtea kollxar udok” goes beyond that. It tries to express the utter futility of anything at all that is said or done with a specific purpose that stays unfulfilled.
A kollso is a large water pot, while umto means upside down. Umto is an adjective used almost adverbially.
A word on what a kollso exactly means. A rather small water pot is called a xidi . A large one is a kollso. (It is rather a coincidence that a kollso is masculine while a xidi is feminine.) A xidi is made of copper. A kollso can also be made of copper, but it is usually made of clay, because a copper kollso full of water is quite a load to carry whereas a clay kollso filled with water is a little lighter.
You may find it interesting that the pronunciation of kollso, as well as that of xidi, is a bit tricky. There is a Konkani word xiddi which means staircase. The dd in xiddi, is a different consonant from the d in xidi. But ask a Spaniard or a Portuguese to pronounce the word xiddi, and you can be almost sure he is going to pronounce it as xidi, because as a rule the Latins, Arabs and many others find it hard to pronounce the hard dd .
There is also a pronunciation problem with the word kollso. In kollso both the Os are open. But if you give the first o a closed sound, i.e., if you make it kôllso , the meaning changes drastically and there is no relationship at all between a kollso and a kôllso. Kôllso stands for coal.