Synonyms for Engrossment (same or very similar meaning)
WordNet sense 1 (complete attention; intense mental effort):
absorption, concentration, immersion
WordNet sense 2 (the mental state of being preoccupied by something):
preoccupation, preoccupancy
WordNet sense 3 (the quality of being intent and concentrated):
intentness
From the ODE community, based on WordNet
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