hollbwysig

From holl (“all”) +‎ pwysig (“important”).

• (North Wales) IPA^(key): /ˌhɔɬˈbʊɨ̯sɪɡ/
• (South Wales) IPA^(key): /ˌhoːɬˈbʊi̯sɪɡ/, /ˌhɔɬˈbʊi̯sɪɡ/

hollbwysig (feminine singular hollbwysig, plural hollbwysig, equative hollbwysiced, comparative hollbwysicach, superlative hollbwysicaf, not mutable)

1. all-important, vitally important, crucial

• hollbwysigrwydd (“quality or state of being all-important, primacy”)

• R. J. Thomas, G. A. Bevan, P. J. Donovan, A. Hawke et al., editors (1950–present), “hollbwysig”, in Geiriadur Prifysgol Cymru Online (in Welsh), University of Wales Centre for Advanced Welsh & Celtic Studies