Medical experts are now suggesting the most likely cause of the very, very slight bump was - to use a technical term - 'lunch'.

Passengers on the train reported the initial impact as nothing more than a slight bump.

Two or three blurred objects flitted past the undercarriage, then they were down, with a slight bump.

Shapes can range from imprint areoles, flat areoles, slight bump or point areoles, full areoles, and combinations of these shapes.

He once described how even slight bumps reduced him to a 'clammier, paler, quicker-pulsed basketcase'.