From Old High German andar halb, literally 'second half'. Anderthalb is the single surviving relic of an older system to describe fractions, which counted from the higher ordinal number rather than the lower cardinal. Compare Old English ōþer healf, and Dutch anderhalf. The word anderer has since lost the meaning 'second', being used solely as 'other' in modern German.
- IPA(key): /andərthalb/, [ˈɑndɐtʰˈhɑlpʰ], [ˈandɐtʰˈhalpʰ] (most of Germany, some of Austria)
- IPA(key): /andərthalb/, [ˈɑnd̥ərtˈhɑlb̥] (Switzerland, some of Austria and southern Germany)
- dritthalb (“two and a half”)
- anderthalb in Duden online