The term "bunky" is a slang word used to describe someone who is unreliable or disappointing. There are a few synonyms that can be used in place of "bunky" to convey a similar meaning. One such word is "flake," which is also used to describe someone who is unreliable. Another synonym for "bunky" is "letdown," as in someone who fails to meet expectations or disappoints others. "Untrustworthy" is another term that could be used in place of "bunky," as it describes someone who can't be relied upon. Ultimately, there are many words that could be used as synonyms for "bunky" depending on the context of the situation.