I don't know if this is right, but to me, thinking is the adjective of thinking the noun not thought the noun. Hence, "A thinking man," but not "thinking flashes" for "flashes of thought." Sentient, to me, is feeling. "A sentient mollusk," for example can't think (?).

But if any one would like to join me, I will be storming Oxford University Press tomorrow at dawn to demand the inclusion of my "memoric" into our lexicon.

Mouthfroth optional.