Com- \Com-\ A prefix from the Latin preposition cum, signifying with, together, in conjunction, very, etc. It is used in the form com- before b, m, p, and sometimes f, and by assimilation becomes col- before l, cor- before r, and con- before any consonant except b, h, l, m, p, r, and w. Before a vowel com- becomes co-; also before h, w, and sometimes before other consonants. [1913 Webster]
COM 1. <programming> {Component Object Model}. 2. <storage> Computer Output on Microfilm - see {Enterprise Report Management}.
com .com dot com <networking> (.com, "commercial") The {top-level domain} originally for American companies but, since the explosion of the {World-Wide Web}, used by most companies and for {vanity domains} of all types, whether in the US or not, often in addition to {country code} domains like amazon.co.uk. The term "dot com" is now widely used to refer to any Internet business as in "My dot com turned into a dot bomb". (2007-02-18)
COM Component Object Model (OLE, OLE2, OCX, ActiveX, MS)