The word "blackenings" can be described using a variety of synonyms. "Darkening," "soot," and "smudging" all signify a discoloration that leans toward black or dark colors. "Obscuring" can imply a covering or hiding of something, while "tarnishing" adds a connotation of damage or decay. "Smeared" and "smudged" focus on the appearance of the blackening, whereas "stained" and "discolored" also highlight the permanence of the mark. "Blotches" and "scorch marks" imply a patchiness or unevenness in the blackening. Overall, there are many words that can be used to evoke a sense of darkness or discoloration when describing the word "blackenings".