(n.) A colored, usually green, expansion growing from the side of   a stem or rootstock, in which the sap for the use of the plant is   elaborated under the influence of light; one of the parts of a plant   which collectively constitute its foliage. 
                        
                    
                    
                        
                        
                            (n.) A special organ of vegetation in the form of a lateral   outgrowth from the stem, whether appearing as a part of the foliage, or   as a cotyledon, a scale, a bract, a spine, or a tendril. 
                        
                    
                    
                        
                        
                            (n.) Something which is like a leaf in being wide and thin and   having a flat surface, or in being attached to a larger body by one   edge or end; as : (a) A part of a book or folded sheet containing two   pages upon its opposite sides. (b) A side, division, or part, that   slides or is hinged, as of window shutters, folding doors, etc. (c) The   movable side of a table. (d) A very thin plate; as, gold leaf. (e) A   portion of fat lying in a separate fold or layer. (f) One of the teeth   of a pinion, especially when small. 
                        
                    
                    
                        
                        
                            (v. i.) To shoot out leaves; to produce leaves; to leave; as, the   trees leaf in May.