18-letter words containing c, h, o, p, l, g
- sociopsychological — of, relating to, or characterized by interrelated social and psychological factors.
- spectroheliography — the process of obtaining an image of the sun in light of a particular wavelength, such as calcium or hydrogen, showing the distribution of the element over the surface and in the solar atmosphere, using a spectroheliograph
- spherical geometry — the branch of geometry that deals with figures on spherical surfaces.
- telephone exchange — a telecommunications facility to which subscribers' telephones connect, that switches calls among subscribers or to other exchanges for further routing.