Sentence:  Elementals are the consciousness guiding the four classical elements of earth, fire, air, and water. These elementals are depicted as <WSD>gnomes</WSD>, salamanders, diminutive faeries known as sylphs, and merfolk, known as undines, respectively. 
Meaning of the word marked with <WSD> tags:  An elemental (spirit or corporeal creature associated with a classical element) associated with earth.