ice: [OE] Ice is a widespread word among the Germanic languages – German has eis, for instance. Dutch ijs, and Swedish and Danish is – but beyond that its connections are somewhat dubious. Some of the more easterly Indo- European languages have or had similar-looking forms, including Old Iranian isu- ‘frosty, icy’, modern Iranian yak ‘ice’, and Afghan asaī ‘frost’, which suggest the possibility of a common source. Iceberg  was perhaps an adaptation of Danish and Norwegian isberg, literally ‘ice mountain’.
Old English is "ice" (also the name of the rune for -i-), from Proto-Germanic *isa- (cognates: Old Norse iss, Old Frisian is, Dutch ijs, German Eis), with no certain cognates beyond Germanic, though possible relatives are Avestan aexa- "frost, ice," isu- "frosty, icy;" Afghan asai "frost." Slang meaning "diamonds" is attested from 1906.
Ice cube attested from 1904. Ice age attested from 1832. To break the ice "to make the first opening to any attempt" is from 1580s, metaphoric of making passages for boats by breaking up river ice though in modern use usually with implications of "cold reserve."