Sentence:  Or , equally often , a concretistic seeming , particularistic seeming statement may consist , with its mundane exterior , in a <WSD>form</WSD> of poetry - may be full of meaning and emotion when interpreted as a figurative expression : a metaphor , a simile , an allegory , or some other symbolic mode of speaking . 
Meaning of the word marked with <WSD> tags:  a category of things distinguished by some common characteristic or quality