verb
To see
To detect
discern implies a making out or recognizing of something visually or mentally to discern one's motives; perceive implies recognition by means of any of the senses, and, with reference to mental apprehension, often implies keen understanding or insight to perceive a change in attitude; distinguish implies perceiving clearly or distinctly by sight, hearing, etc. he distinguished the voices of men down the hall; observe and notice both connote some measure of attentiveness, though the former may imply a more conscious act of will, and both usually suggest use of the sense of sight to observe an eclipse, to notice a sign
See discern in Webster's New World Roget's A-Z Thesaurus II
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