English has a whole toolbox of words for how hard something is, and each tool does a different job. A climb can be arduous, a duty onerous, a copying job laborious, a race grueling. A rival can be formidable, a box cumbersome, a ladder precarious. And some tasks are hopeless (futile) or much too easy (facile).
Key idea
Hard work: arduous (steep, demanding), onerous (a heavy burden), laborious (slow and painstaking), grueling (exhausting). Hard to face or handle: formidable, cumbersome, precarious. No use: futile. Easy: effortless (praise) and facile (usually blame).
The Latin inside helps: arduus meant steep, onus a load, labor work, formido fear, and facilis easy.
The ten words
Common mistake
facile is usually a criticism (a facile answer), not praise. onerous means burdensome; it has nothing to do with honor.
| word | what makes it hard | picture it |
|---|---|---|
| arduous | steep, demanding effort | a long uphill climb |
| onerous | a heavy duty or burden | a pile of paperwork |
| laborious | slow, painstaking work | copying a book by hand |
| grueling | it wears you out | a fifty-mile race |
| formidable | it is strong or scary | a champion rival |
| cumbersome | awkward and bulky | a suitcase with no wheels |
| precarious | it could fall or fail | a wobbly stack of plates |
Common mistake
facile sounds like praise (it shares a root with facility, ease), but it is usually a criticism: a facile answer is too easy to be any good. If you mean easy in a good way, choose effortless. And onerous (a burden, from onus) has nothing to do with honor.