Wordnet 3.0
ADJECTIVE (1)
1. 
 attached directly by the base; 
 not having an intervening stalk; 
- Example: "sessile flowers"- Example: "the shell of a sessile barnacle is attached directly to a substrate"[syn: sessile, stalkless]
The Collaborative International Dictionary of English v.0.48:
Stalkless \Stalk"less\, a.
   Having no stalk.
   [1913 Webster]
WordNet (r) 3.0 (2006):
stalkless
    adj 1: attached directly by the base; not having an intervening
           stalk; "sessile flowers"; "the shell of a sessile
           barnacle is attached directly to a substrate" [syn:
           sessile, stalkless] [ant: pedunculate, stalked]