I heard the Messenger of Allah ﷺ say it. Ibn Umar then said, "We have surely lost out on a great many measures of reward." The word "neglected" here means to have squandered something of Allah's command.
فصدقت يعني
سمعت رسول الله ﷺ يقوله فقال ابن عمر رضي الله عنهما لقد فرطنا في قراريط كثيرة {فرطت} ضيعت من أمر الله