Asynchronous is a term that indicates that precise relative timing is not needed for two or more input signals entering a circuit, or two or more sets of gliders participating in a glider synthesis. In some cases the signals or sets of gliders can arrive in any order at all -- i.e., they have non-overlapping effects.
However, in some cases such as slow salvo constructions, there is a required order for some of the incoming signals. These signals can still be referred to as "asynchronous" because the number of ticks between them is infinitely adjustable: arbitrarily long delays can be added with no change to the final result.
- Asynchronous at the Life Lexicon