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Understood (7 letter answer)
The answer GRASPED is so rare that it appears less than once every 2500 puzzles.
GRASP as a verb:
1. (grasp, hold on) = hold firmly
2. (grok, get the picture, comprehend, savvy, dig, grasp, compass, apprehend) = get the meaning of something; "Do you comprehend the meaning of this letter?"