sem·i·di·ur·nal 
(sĕm′ē-dī-ûrnəl, sĕm′ī-)
(sĕm′ē-dī-ûrnəl, sĕm′ī-)adj.
1. Of, relating to, occurring, or performed during half a day.
2. Occurring or coming approximately once every 12 hours, as the tides.
3. Of or relating to the arc described by a celestial body between its meridian passage and its points of rising or setting.
- accessible
- accessibleness
- accessibly
- accession
- accessional
- accessorial
- accessorily
- accessorize
- accessory
- accessory after the fact
- accessory apartment
- accessory before the fact
- accessory fruit
- accessory mineral
- accessory nerve
- accessory pigment
- access road
- access time
- acciaccatura
- accidence
- accident
- accidental
- accidentally
- accident insurance
- accidently