dheub- / Indo-European roots
1. deep, depth from Old English dēop, deep, from Germanic *deupaz.
2. dip from Old English dyppan, to immerse, dip, from Germanic expressive denominative *duppjan.
3. Parallel root form *dheubh-. dive1 from Old English dȳfan, to dip, and dūfan, to sink, dive, from Germanic verb *dūbjan, from *deub-, *dub-.
4. Suffixed parallel root form *dhū̆bh-(o)n-, with expressive variants. python, Python1, Typhon from Greek Pūthōn and Tuphōn, mythical monsters, from *dhub(h)-n- and *b(h)ud(h)-n-, which already in Indo-European were doublets by inversion, referring to "bottom" "foundation" "depths" and the mythological monsters that inhabited them.
[Pokorny dheu-b- 267.]