1. Lacking sense or discretion
   - rattlebrained, rattlepated, scatty [Brit] 
2. Guided by whim and fancy
   - flighty, flyaway, head-in-the-clouds

See also: foolish, frivolous

• scene
• scene of action
• scene painter
• scene-stealer
• scenery
• sceneshifter
• scenic
• scenic artist
• scenic railway
• scenically
• scenography
• scent
• scent out
• scented
• scented fern
• scented penstemon
• scented wattle
• scentless
• scentless camomile
• scentless false camomile
• scentless hayweed
• scentless mayweed
• scepter
• sceptered
• sceptic