| Word | Definition |
|---|---|
| carbon-based adj. (1939) | based on the chemistry of carbon compounds: usually describing life, contrasted with that based on other chemical elements |
| carbonite n. (1980) | a carbon-based material in which a person can be cryogenically preserved |
| catastrophe adj. (1948) | = disaster adj. |
| Centaurian n. (1931) | a native or inhabitant of the constellation Centaurus or of a star system within it, esp. Alpha Centauri; cf. Alpha Centaurian n. |
| Centaurian adj. (1901) | of or relating to the constellation Centaurus or one of its star systems, esp. Alpha Centauri, or its inhabitants; cf. Alpha Centaurian adj. |
| Chicon n. (1940) | a SF convention held in Chicago, esp. the 1940 Chicago Science Fiction Convention |
| chrononaut n. (1960) | = time traveller n. |
| chronoscope n. (1936) | a device for viewing events in the past or future |
| chronoscopy n. (1956) | viewing past or future events |
| Clarke belt n. (1981) | the ring-shaped region around the Earth containing all possible geostationary orbits |
| Clarke orbit n. (1969) | geosynchronous orbit |
| Clarke’s Law n. (1962) | any of three maxims formulated by Arthur C. Clarke (sometimes specified as Clarke’s First Law, Clarke’s Second Law, Clarke’s Third Law): (a) ‘When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong’ (b) ‘The only way of discovering the limits of the possible is to venture a little way past them into the impossible.’ (c) ‘Any sufficiently advanced technology is indistinguishable from magic’ |
| class M planet n. (1964) | an Earth-type planet |
| cloak v. (1984) | to make invisible or undetectable, esp. by means of a cloaking device n. |
| cloaking device n. (1968) | a device for rendering something invisible or undetectable |
| clone n. (1970) | any member of a hypothetical population of artificially produced, identical people, aliens, etc. Also: a duplicate of a living person |
| COA n. (1961) | notification of a change of address |
| cold fusion n. (1956) | nuclear fusion taking place at temperature lower than ordinarily required, spec. at or near room temperature |
| cold sleep n. (1941) | a form of suspended animation in which the subjects are kept at very cold temperatures |
| cold sleep v. (1956) | to undergo suspended animation for a period of time; (transitive) (rare) to put a person into cold sleep n. |
| cold sleeper n. (1969) | a person in cold sleep |
| collapsium n. (1958) | any of a variety of extremely high-density substances |
| commlink n. (1974) | a communication link; a communication device |
| communicator n. (1934) | a device for communicating with a spaceship or astronaut |
| completism n. (1944) | the desire to have or collect a complete set of something |
| completist n. (1944) | one who wishes to have or collect complete sets of some particular items |
| con n. (1942) | a convention of a group of (usually and originally science fiction) fans; cf. -con suffix |
| -con suffix (1940) | (used to form the names of conventions, with the first element indicating the location or (typically in informal designations) the main subject or focus of the event) cf. con n. |
| con crud n. (2014) | an illness (esp. a cold) suffered while or shortly after attending an SF convention |
| condom n. (1986) | the milieu of (usually science fiction) conventions |
| congoer n. (1954) | one who attends (usually science fiction) conventions |
| congoing n. (1959) | attendance at (usually science fiction) conventions |
| conlang n. (1991) | an artificially created language; esp. a language invented to represent the speech of an alien race |