From Longman Dictionary of Contemporary Englishbe miles awaybe miles awayspokenATTENTION to not be paying attention to anything that is happening around you ‘Kate!’ ‘Sorry, I was miles away!’ → mile
Examples from the Corpus
be miles away• I don't mean to disturb you, you looked miles away -- but there's a call for you.• Given that the factory producing the chocolate is miles away, the resulting confections are really quite good.• Sorry, I was miles away. What did you say?• I was miles away from the possibility of victory tonight.• First, the man was miles away in London.• Her mind was miles away, focused on imaginary scenarios being played out between Piers and Nicole.• Whoever it was must be miles away by now.• Their great protector was miles away, engrossed in Parcheesi.• For a moment there you seemed to be miles away.• That was the image that occurred to me, but by the time I thought of it we were miles away. 