Thinking unhappily or anxiously about something; moody and withdrawn, or (in birds) ready or eager to sit on eggs to hatch them.
From brood + the adjective suffix '-y'. This combination creates an adjective describing the state of brooding.
A broody hen is literally willing to sacrifice food and water to sit on eggs for weeks—so when we call a person broody, we're saying they're that focused on dark thoughts, which is pretty intense poetry actually.
Complete word intelligence in one call. Free tier — 50 lookups/day.