stalker

intransitive verb

1. 1. to walk in a stiff, haughty, or grim manner
   2. to advance or spread grimly: plague stalks across the land
2. to pursue or approach game, an enemy, etc. stealthily, as from cover
3. Obsolete to walk or move along stealthily or furtively

transitive verb

1. to pursue or approach (game, prey, etc.) stealthily
2. to stalk through: terror stalked the streets
3. to follow or pursue (another person) persistently in a harassing and, typically, obsessive way

noun

1. a slow, stiff, haughty, or grim stride
2. the act of stalking game, an enemy, etc.