Definition of on the part of (or on my, their, etc., part) in US English:

on the part of (or on my, their, etc., part)

phrase

  • Used to ascribe responsibility for something to someone.

    ‘there was a series of errors on my part’
    • ‘I think it was good to promote safe and responsible drinking on their part.’
    • ‘In retrospect, it's clear that we regarded that as an error on their part.’
    • ‘But it was a major error on their part to attack the U.N. It does show they are getting desperate.’
    • ‘It transpires that it was a clerical error on their part - obviously - and a huge one too.’
    • ‘Similarly there is a responsibility on the part of the walker to honour the deal.’
    • ‘There was very little mind reading required on my part as to what was going on, and he made space for us to do a family outing as well.’
    • ‘My initial instinct is to take her side, but that's fairly obviously just a knee-jerk response on my part.’
    • ‘You definitely deserved some of it, but a lot of it was error on my part, and I'm sorry.’
    • ‘So there is a bit of responsibility on my part not to treat it as a gimmick.’
    • ‘The Institute concede there was an error on their part, but insist the athlete must bear some responsibility too.’
    by, made by, done by, carried out by, caused by, from, in, of
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