Finding and mapping related concepts is a bit more challenging than merely matching occurences with a specific term. Unless you can locate a WWW search mechanism that allows you to truncate terms using wildcards you may have difficulty in finding other "meta" terms. There is, of course, the option of using an on-line dictionary. You may have even tripped across a useful list in performing a search for "metacognition". You may have even forced a connection by conducting a Boolean search for ("metacognition" and ("list" or "terms")) or some such combination.
Online learning does not preclude the use of off-line tools. Don't forget that users and machines are embedded in environments. There may be a set of reference tools at hand. Here are two sources for other "meta" terms:
As you can begin to determine, cognition has much to do with communication. Thinking about communication can helps us think about thinking if only because the act of thinking is like a constant dialogue, a perpetual round of questions and answers.