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.