Wordnet 3.0
ADJECTIVE (1)
1. 
 of inferior status or quality; 
- Example: "a second-class citizen"- Example: "second-class accommodations"
The Collaborative International Dictionary of English v.0.48:
Second-class \Sec"ond-class`\, a.
   Of the rank or degree below the best or highest; inferior;
   second-rate; as, a second-class house; a second-class
   passage; a second-class citizen.
   [1913 Webster +PJC]
WordNet (r) 3.0 (2006):
second-class
    adj 1: of inferior status or quality; "a second-class citizen";
           "second-class accommodations"