The suffix "-al" is often used to pass along the idea of <em>"Like"</em> or <em>"Suitable for"</em>.
You can see that in words like: <em>Spacial</em>, which is most likely <em>"Suitable for Space"</em> (Spacial Awareness, for example) and Optional, which is something that <em>"fits an Option"</em> (as in, something that will not be mandatory).
