show: [OE] Show originally meant ‘look at’. Its modern senses – basically ‘cause to look at’ – did not begin to develop until the early Middle English period. It comes from a prehistoric West Germanic *skauwōjan, whose German descendant schauen still means ‘look at’ (and whose Flemish descendant scauwen gave English scavenger). This in turn was derived from the base *skau- ‘see, look’, source also of English sheen and German schön ‘beautiful’.
And the ultimate ancestor of *skau- was an Indo- European base which also produced Greek keein ‘observe’ and Latin cavēre ‘beware’ (source of English caution [13] and caveat [16]). => caution, caveat, scavenger, scone, sheen[show etymology, show origin, 英语词源]