Squid defined..?
Indeed, easier said than done... It's a term still in evolution, which seems to indicate a sportbike pilot who manifests some degree of skill, usually somewhat compromised by a lack sound judgement as he/she is prone to periodically exercise the application of those skills at inappropriate times and places... like maximum velocity in normal (public) traffic environments. Surprisingly, the skill level can be quite high and expectation of survival is a fairly high probability.
Conversely, at the other end of the skill/performance scale can be found those increasingly refered to as squiggs (from the English squiggle, which refers to the residual mark usually left on the pavement immediately prior to departure from the current skill envelope). Think of a squigg as a wannabe squid, but currently deficient in prerequisite survival skills... a sort of tadpole to potential frog analogy, if you will.
These are merely observations of what appears to be a dynamic evolution of motorcycling terms, rich in imagination and imagery. Lack of self-awareness on this scale and appreciation thereof seems to be in inverse proportion to the maturity level of the rider.
I hope you find this observation useful.