Most communications systems are intensely dependent upon the order in which you transmit information. For example, a binary code, like Morse Code, cannot convey information unless the order of the dots and dashes is strictly controlled and can be reliably transmitted. But, what about the opposite situation?
Imagine a language that evolve in, or was designed for, a context where you could not be assured of the order in which your words were transmitted.
Maybe it was usually transmitted one word at a time carrier pigeon-style by insects that could only carry one word each and traveled in swarms, or by groups of balloons carrying one word each whose order could be jumbled by air currents, or by sounds contained in bubbles whose flow through water could be jumbled by water currents, or by sound in caves with such intense echoes that the order of the words would be heard could not be reliably predicted, or by spies none of whom could be trusted with the entire message whose duration of travel could not be easily predicted relative to each other.
Suppose also that any of these potential methods of communication has a fairly high rate of losing words in transmission, maybe 2%-5% of the words transmitted would be lost in a typical communication (something that would seem likely to be the case in any of the examples of a means of communication where word order would be routinely compromised).
What features would a language that works well in these conditions have to have to function?
Real world examples of languages developed for use in these conditions, if any, would obviously be one way to provide a convincing an answer, although not necessarily the only one.