
1) Plant part 2) Plant structure 
Found on 
https://www.crosswordclues.com/clue/ligule

(1) small membranous appendage on the top of the sheath of grass leaves; (2) a minute adaxial appendage near the base of a leaf, e.g. in Selaginella; (3) extended, strap-like corolla of some daisy florets.
Found on 
http://en.wikipedia.org/wiki/Glossary_of_botanical_terms

 A ligule (from ligula `strap`, variant of lingula, from lingua `tongue`) — is a thin outgrowth at the junction of leaf and leafstalk of many grasses (Poaceae) and sedges or a strap-shaped corolla, such as that of a ray floret in plants in the daisy family. ==Poaceae and Cyperaceae== The ligule is part of the leaf, and is found at the junctio...
Found on 
http://en.wikipedia.org/wiki/Ligule

outgrowth from the inner junction of the grass leaf sheath and blade, often membranous, sometimes represented by a fringe of hairs. Also a small, membranous, triangular organ on the adaxial side of the fertile leaf base in Isoetes or the narrow, upper part of a reduced petal in some Sterculiaceae or the single corolla lobe of a floret of Asteraceae...
Found on 
http://florabase.dpaw.wa.gov.au/help/glossary

a thin membraneous appendage at the apex of a leaf sheath
Found on 
http://orchidfetish.com/glossary.html

• (n.) A strap-shaped corolla of flowers of Compositae. • (n.) A band of white matter in the wall of fourth ventricle of the brain. • (n.) The thin and scarious projection from the upper end of the sheath of a leaf of grass.
Found on 
http://thinkexist.com/dictionary/meaning/ligule/

Structures that occur where the leaf blade attaches to the stalk.
Found on 
http://urbanext.illinois.edu/veggies/glossary.cfm

papery structure 1 mm or so which marks the junction between a leaf sheath and its blade and is in the same plane as the sheath; together with the auricle is it called the leaf collar.
Found on 
http://wheatdoctor.org/glossary?showall=&start=1

(from the article `Lycophyta`) Another distinctive feature in Selaginella is the presence of an unusual structure on the adaxial side of a leaf; this is the ligule, a peculiar ...
Found on 
http://www.britannica.com/eb/a-z/l/50

A strap-shaped structure, a membranous or hairy appendage on the adaxial surface of a leaf, especially in grasses, at the junction between sheath and blade. ... (09 Oct 1997) ... 
Found on 
http://www.encyclo.co.uk/local/20973

In grasses and grasslike plants, a membranous or hairy extension arising from the inside of the leaf sheath at its juncture with the blade; a straplike structure; in the Asteraceae, the straplike corolla of a ray floret.
Found on 
http://www.encyclo.co.uk/local/22034

A structure on the inside at the junction of the leaf blade and leaf sheath.
Found on 
http://www.encyclo.co.uk/local/22037

in the grasses (Gramineae), a papery extension at the summit of a leaf sheath.
Found on 
http://www.encyclo.co.uk/local/22043

The appendage or ring of hairs on the inside of grass leaves where the sheath and blade join.
Found on 
http://www.encyclo.co.uk/visitor-contributions.php
 Lig'ule
Lig'ule (-ul) 
 noun [ Latin 
 ligula , 
 lingula , little tongue, dim. of 
 lingua tongue : confer French 
 ligule .] 
 1.  (Botany)  (a)  The thin and scarious projection from the upper end of the sheath of a leaf of grass. 
 (b)  A strap-shaped corolla of f...
Found on 
http://www.encyclo.co.uk/webster/L/41

A strap-shaped organ or body; particularly, a strap-shaped corolla, as in the ray-flowers of composites; also a projection from the top of the sheath in grasses and similar plants.
Found on 
http://www.gardenology.org/wiki/Glossary_of_Gardening_Terms

a thin membraneous appendage at the apex of a leaf sheath
Found on 
http://www.orchidspecies.com/glossary.htm
 noun
 noun (botany) any appendage to a plant that is shaped like a strap
Found on 
https://www.encyclo.co.uk/local/20974

A protruding structure from the upper surface of the leaf where the blade and the sheath are joined.  This structure may be membranous, a fringe of hairs or a membrane with hairs.  The ligule can vary in both shape and size and may also be absent.  
Found on 
https://www.encyclo.co.uk/local/22488
  No exact match found.