adjective / verb
busy
BIZ-ee/ˈbɪzi/
Full of activity or demands on attention.
The busy cook checks a pot while preparing vegetables and watching the timer.

Etymology
Old English bisig included the idea of being careful or anxious, as well as occupied. The anxious element faded, leaving the modern emphasis on being engaged in work or activity.
In context
best brains in the world are busy solving problems of the rich who really don't have problems to solve
More examples
- She busied herself sorting the mail.
- The wallpaper looked too busy beside the patterned curtains.
- I tried calling again, but the line was busy.
Forms
busy · busier · busiest · busies · busied · busying
Similar words
- occupied
- Engaged or in use, while busy also suggests many competing activities.