What is the history of the word gangster?

Gangster came into the English language at the latter portion of the 19th century, as one of what is now a large parcel of words which have been formed by adding the noun combining form –ster to an existing word. The ending -ster has a number of possible meanings (“one that does, handles, or operates,” “one that makes or uses,” “one that is associated with or participates in,” “one that is”), and one of its interesting elements is that it has, in many cases, shifted its gender. This second portion of gangster comes from the Old English -estre, meaning “female agent.” The word tapster ("a bartender"), for instance, was tæppestre in Old English, and designated a barmaid, or female tapster. In modern use the addition of -ster may often be found in a gender-neutral sense, as with hipster, or with implications of masculinity, as with gangster and mobster, through prevalence of usage.