From Longman Dictionary of Contemporary Englishpick up on something phrasal verb1 NOTICEto notice something about the way someone is behaving or feeling, even though they are trying not to show it Children pick up on our worries and anxieties.2 DISCUSSto return to a point or an idea that has been mentioned and discuss it more I’d like to pick up on a point that Steven made earlier.3 pick somebody up on somethingCRITICIZE to criticize someone slightly for something they have said I knew he was lying and I should have picked him up on it. → pick→ See Verb table
Examples from the Corpus
pick up on • It was downright sinister and the fact that Glyn had picked up on her uneasy feelings left her more uneasy still.• I hadn't picked up on it, and he had no hand at all in your coming to work for me.• The girls pick up on the excitement of the crowd and come out strong.• It is important that a manager pick up on the good particularly and show them how to use it.• Carolyn was picking up on the movements of the three women, which had seemed so mysteriously random at first.• There's a lot of frequencies you can't pick up on the record listening through small speakers.• Unfortunately, children pick up on this response.pick somebody up on something• When they went off the air in the evening, I picked it up on my program.• We used to keep it round Nezzer Eyres's and pick it up on Sundays when we wanted it.• A Sergeant and four Corporals arrived from Orange to pick us up on the following Monday.• He says they picked it up on the radar and had to take evasive action. 