Wordnet 3.0
NOUN (1)
1. 
 a time assigned on a schedule or agenda; 
- Example: "the TV program has a new time slot"- Example: "an aircraft landing slot"[syn: time slot, slot]
WordNet (r) 3.0 (2006):
time slot
    n 1: a time assigned on a schedule or agenda; "the TV program
         has a new time slot"; "an aircraft landing slot" [syn:
         time slot, slot]