[com-] or col- or con- prefix [ME, fr. OF, fr. L, with, together, thoroughly--more at co-]: with: together: jointly--usu. com- before b, p, or m "commingle", col- before l "collinear", and con- before other sounds "concentrate"
COM-
Meaning of COM- in English
Merriam-Webster English vocab. Английский словарь Merriam Webster. 2012