Macquarium

The story

1. Proto-Celtic*makkʷos
2. Old Irishmacc
3. Middle Irishmac
4. Scottish Gaelicmac
5. Scottish Gaelican
6. Proto-Celtic*to-
7. Proto-Indo-European*weyd-
8. Proto-Indo-European*wéydtus
9. Proto-Celtic*wissus
10. Proto-Celtic*towissus
11. Proto-Celtic*towissākos
12. Old Irishtoísech
13. Scottish Gaelictòisiche
14. Scottish GaelicMac an Tòisiche
15. EnglishMcIntosh
16. EnglishMacintosh
17. EnglishMac
18. Proto-Indo-European*h₂ékʷeh₂
19. Proto-Italic*akʷā
20. Latinaqua
21. Latinaquārium
22. Englishaquarium
23. English todayMacquarium

Blend of Mac + aquarium, coined by computer writer and Macquarium creator Andy Ihnatko (originally as a joke regarding the approaching obsolescence of early Compact Macintosh models).