painstaking

US /ˈpeɪnzˌteɪ.kɪŋ/
UK /ˈpeɪnzˌteɪ.kɪŋ/
"painstaking" picture
1.

minutieux, soigneux, laborieux

done with great care and thoroughness

:
The artist made a painstaking effort to capture every detail.
L'artiste a fait un effort minutieux pour capturer chaque détail.
It took years of painstaking research to complete the book.
Il a fallu des années de recherches minutieuses pour achever le livre.