Definitions of stalk:

• noun:   a stiff or threatening gait
• noun:   the act of following prey stealthily
• noun:   a hunt for game carried on by stalking or waiting in ambush
• noun:   a slender or elongated structure that supports a plant or fungus or a plant part or plant organ
• noun:   material consisting of seed coverings and small pieces of stem or leaves that have been separated from the seeds
• verb:   walk stiffly
• verb:   go through (an area) in search of prey

  Example: "Stalk the woods for deer"

• verb:   follow stealthily or recur constantly and spontaneously to

  Example: "Her ex-boyfriend stalked her"