Meaning: This sentence conveys the idea that even in the midst of winter's harshness, there can be pockets of warmth and comfort, symbolized by the snowman's heart.
Choice of Words: "Snowman's heart" refers to the center or core of the snowman. "Warmth" is a noun that refers to a feeling of heat or comfort. "Winter's chill" refers to the cold and harsh conditions of winter. "Snowman's heart, warmth in winter's chill" suggests that the snowman, despite being made of snow and ice, possesses a source of warmth and comfort that defies the coldness of winter.