- chalice
- chalicothere
- Chaling
- Chaling Xian
- Chaliubieju
- chalk
- chalkbrood disease
- Chalk Drawing
- chalkography
- challenge
- challenge handshake authentication protocol
- challenge handshake authentication protocol, CHAP
- challenge-response authentication
- Challenger Space Shuttle
- Challenging Minisatellite Payload
- Challis crater
- chalone
- Chalukouporphyry molybdenum deposit
- Cham
- chama
- Chamaeleon
- chamaephytes
- Chamber
- chamber
- chamber and slot classifier