Synonyms for Detection (same or very similar meaning)
WordNet sense 1 (the detection that a signal is being received):
signal detection
WordNet sense 2 (the perception that something has occurred or some state exists):
sensing
WordNet sense 3 (a police investigation to determine the perpetrator):
detecting, sleuthing, detective work
WordNet sense 4 (the act of detecting something; catching sight of something):
catching, espial, spotting, spying
From the ODE community, based on WordNet
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