n. (pl. geniuses or genii) 1 (pl. geniuses) a an exceptional intellectual or creative power or other natural ability or tendency. b a person having this. 2 the tutelary spirit of a person, place, institution, etc. 3 a person or spirit regarded as powerfully influencing a person for good or evil. 4 the prevalent feeling or associations etc. of a nation, age, etc.
[ L (in sense 2) f. the root of gignere beget ]