Onerous (adj)
on-ur-us
burdensome, oppressive, or troublesome; causing hardship
First recorded between 1350–1400. From the Latin root onus, meaning “burden,” from which we also get the English onus.
Example sentences
“The hike became more onerous as the trail became muddier in the rain, and the dark clouds moved in.”

Soigné (adj) swahn-yay Carefully or elegantly done, operated, or designed First recorded in 1915–20. Borrowed directly from French; originally from soin, meaning “care.” (more…)