Wordnet 3.0
ADJECTIVE (1)
1. 
 designed to promote discipline; 
- Example: "the teacher's action was corrective rather than instructional"- Example: "disciplinal measures"- Example: "the mother was stern and disciplinary"[syn: corrective, disciplinary, disciplinal]
The Collaborative International Dictionary of English v.0.48:
Disciplinal \Dis"ci*plin*al\, a.
   Relating to discipline. --Latham.
   [1913 Webster]
WordNet (r) 3.0 (2006):
disciplinal
    adj 1: designed to promote discipline; "the teacher's action was
           corrective rather than instructional"; "disciplinal
           measures"; "the mother was stern and disciplinary" [syn:
           corrective, disciplinary, disciplinal]