Labor-intensive (adjective)

Requiring a large amount of physical or mental effort.

Origin:

From the combination of the words labor and intensive, referring to the intensive use of labor or human effort in a particular process or activity.

Examples:

1. The construction of the building was labor-intensive.
2. The project was labor-intensive and required a lot of manual work.
3. The process of making handmade crafts is labor-intensive.
4. The job was labor-intensive, with long hours and heavy lifting.
5. The manufacturing process was labor-intensive and required skilled workers.