sci

know

Spelled sci · Latin scire 'to know,' with participle sciens 'knowing'

Latin scire meant know: science seeks knowledge, conscious people are aware, and an omniscient narrator knows every character's thoughts.

Words built from it

science — systematic study of the world through evidence and testing
Latin scire (know) → scientia (knowledge) → English science
conscious — awake and aware of oneself or one's surroundings
Latin con- (with) + scire (know) → conscius (sharing knowledge, aware) → conscious
omniscient — knowing everything
Latin omnis (all) + sciens (knowing), from scire (know)
prescience — knowledge of events before they happen
Latin prae- (before) + scientia (knowledge), from scire (know) → praescientia
nescient — lacking knowledge or awareness
Latin ne- (not) + sciens (knowing), from scire (know) → nesciens
unconscious — not awake and aware; also, occurring without awareness
English un- (not) + conscious, from Latin con- (with) + scire (know)

fascinate — Contains sci, but comes from Latin fascinare 'to bewitch,' unrelated to scire 'to know.'
scintillate — Contains sci, but comes from Latin scintillare 'to sparkle,' from scintilla 'spark.'