Object clearly visible but shape not clear and not behaving like an aircraft

Object looked close enough to identify with binoculars - shape unclear but did not look like a plane. I commented immediately and others began watching also. Moving more slowly than an aircraft. Travelling in a southerly direction but seemed to hover at times and change course. It had been large enough or close enough to be able to follow for some time but it suddenly disappeared whilst we were trying to find it to look through binoculars. Blue skies and very good visibility. Left no trail.