time-consuming

time-consuming (comparative more time-consuming, superlative most time-consuming)

1. Using significant amounts of time, especially in an unwanted and sometimes unwarranted manner.
   • 2019, Li Huang, James Lambert, “Another Arrow for the Quiver: A New Methodology for Multilingual Researchers”, in Journal of Multilingual and Multicultural Development, →DOI, page 11:

     However, given current sensibilities about individual privacy and data protection, the recording of oral data is becoming increasingly onerous for researchers who are obliged to navigate an often time-consuming and complex series of administrative requirements and corollary review processes in order to be granted ethics clearance.

• chronophagous (rare)
• time-taking (dated)