Mark Clifton

astronavigator n.	1960 M. Clifton Eight Keys to Eden (1965) 22 Sure, it was only a three-man crew—himself, a flight engineer, an astro-navigator.
escape ship n.	1960 M. Clifton Eight Keys to Eden xiii. 83 They were all for taking the escape ship and hightailing it back to Earth.
gravitied adj. 1	1962 M. Clifton Hang Head, Vandal! in Amazing Stories Apr. 16/2 We assembled the mastership on the Moon base from parts which were Roman candled up, a few pieces at a time, from too heavily gravitied Earth.
spacegram n.	1953 M. Clifton Bow Down to Them in Universe Science Fiction June 84/2 ‘Oh, by the way, a space gram came for you a while ago.’ He reached over to one corner of his desk and dug the gram out from under some prints.
space sailor n.	1953 M. Clifton Bow Down to Them in Universe Science Fiction June 85/2 Admiral Littlefield was a space sailor of the old school.