I have a clear memory of the first time I heard the word skiver. It was my first year, the first weeks probably, in Grammar School. Our class (1E) was in a demountable classroom near the woods - out of bounds, of course. From the woods we heard singing it was Chirpy chirpy cheep cheep by Middle of the Road. A helpful voice said "Skivers miss". I wasn't a hundred per cent sure what the word meant but no doubt it referred to what I had until then known as moochers (everyone else says mitchers). I think I assumed that skiving from Junior School was mooching and mooching from big school was skiving. Mark Twain called it playing hookey I later discovered.I see mooch is listed here
mooch Verb. 1. To idle away time, to loaf around. E.g."The kids were just mooching about the streets looking for something to do." 2. To amble along, to walk casually. 3. To play truant. [Welsh use] Noun. 1. The idling away of time. 2. The act of ambling or walking casually. E.g."I'm going for a mooch around the shops."