The term 'SPREADING OUT FROM THE CENTRE' can be summarized by the word 'RADIAL', which is a 6-letter word. RADIAL is an adjective that describes something that is arranged in a circular pattern, with lines or objects extending out from a central point. This type of arrangement is often seen in nature, such as the petals of a flower or the spokes of a wheel. It can also be used to describe the layout of a city or other urban area, with streets radiating out from a central point.