Definitions of tiller:

• noun:   lever used to turn the rudder on a boat
• noun:   someone who tills land (prepares the soil for the planting of crops)
• noun:   a shoot that sprouts from the base of a grass
• noun:   a farm implement used to break up the surface of the soil (for aeration and weed control and conservation of moisture)
• verb:   grow shoots in the form of stools or tillers
• name:  A surname (rare: 1 in 33333 families; popularity rank in the U.S.: #4214)