A leg is (to be as general as possible) a bodily structure which extends from the main body in an articulated chain of linear solids and can be moved in a variety of patterns. It is naturally one of a pair (we want to exclude tails to avoid old Lincoln jokes) of roughly symmetric extensions. A foreleg is a leg of the pair (occasionally perhaps two or more pairs) closest to the head of the body. Typically, such legs end in a facile organ, though the nature of this organ – and of the leg as a whole – varies greatly from one species to another. These range from being used to grasp things to wings, with many odds and ends in between, including not being significantly different from the other legs of the animal in question.
The point of all this is that there is a single concept here, even though we use a number of different words in English: arm and hand, leg and paw or hoof, wing, claw or pincher, etc. That concept can be subdivided into subordinate concepts based on what animal is involved (human arms and cats
legs) or how the structure works out (elbow and wrist vs, knee and ankle) or what use is central (grasping , feeding, locomotion, …) or countless other ways. These subdivisions do not make a word attached to this concept in a language polysemic. Thus, the word ‘luka’ in toki pona is not polysemic because we may translate it into English as, depending on context, “arm”, “leg” “claw”, “wing” and so on.
But the toki pona word ‘luka’ is polysemic, because it also means “five”. There are no semantic connections between a number and a body part, whereby we might say that the concept merely expanded into a neighboring territory (a bad way of putting it, technically, but clear). The two concepts are simply distinct in every way. To be sure, there are factual and historical reasons why the same word might be used for both, but these have nothing to do with meaning. ‘luka’ simply has two different meanings. We cannot say – as we occasionally do in English – that there are two different words here, each with a single meaning, that just happen to turn out ot look and sound alike. The history of ‘luka’ in toki pona is too clear to allow that.
Curiously, when discussion turns to polsemy (“ambiguity”) in toki pona, ‘luka’ is seldom mentioned. Indeed, the usual target is ‘wile’, which is translated into English variously as “need, want, must, should, ought, necessary” and the like. But, as noted above, the various translations in various contexts is not a sign of a number of concepts but may be just the result of English forcing subdivisions on a single concept. This is the case here. The toki pona word ‘wile’ is the strong modal, meaning, roughly, “the subject is subject to an overwhelming force to do the indicated thing”. The source of the force may be internal desires, external social or economic pressures, or the laws of nature or logic; ‘wile’ does not need to specify. Nor need the “overwhelming” be taken too strictly, since such forces can conflict and only one win out. If we need (which as English (etc.) speakers we seem to do) to distinguish, it is up to us to provide the relevant context or information to make the case for the various English translations (specifications of subdivisions). But doing so is not disambiguating the toki pona, it is merely satisfying some English (etc.) requirement.
In conclusion, we ought not say that toki pona is ambiguous or more ambiguous than some other language if our evidence is merely that other languages are more generous will giving words to semantic subconcepts. Toki pona has only 120+ words, so its concept assignments must be to very broad concepts. This is not to say that toki pona does not have polysemic word, even beyond, ‘luka’, again largely thanks to the small vocabulary size. But, given the actual considerable polysemy of such enormous languages as English, it hardly seems fair to attack toki pona on this issue.