Prefix · relation · together with
Means "together" or "with": connect, combine, cooperate, communicate, compare.
Written by Bryan López, English teacher · Updated
Con-/com- comes from Latin "cum" (with, together) and signals that something happens jointly or between multiple parts: connect = bind together; combine = join together; communicate = share together; compare = bring together for examination; compete = strive together. It is one of the most common prefixes in English and generates hundreds of Latin-based words.
The form changes based on the following sound: com- before b, m, and p (combine, command, compete, communicate); co- before vowels and h (cooperate, coexist, coauthor, cohere); con- before most other consonants (connect, confirm, contrast, control, concern). This phonetic assimilation is the same rule as in Spanish (combinar, cooperar, conectar).
Attaches to verbs and nouns to express joint action or relationship:
Pronunciation: /kɒn/ (con-), /kəm/ (com-), /kəʊ/ (co-). Spanish cognates are massive and direct: connect/conectar, combine/combinar, compare/comparar, compete/competir, confirm/confirmar, communicate/comunicar, cooperate/cooperar.
con-/com-/kɒn/ /kəm/
Tap the button to hear how the prefix sounds. Each word in the table has its own audio.
Phonetic assimilation rule — the same as in Spanish: "con + bine" → combine (not "conbine"); "con + operate" → cooperate (not "conoperate"); "con + firm" → confirm. The assimilation is predictable: bilabial consonants (b, m, p) attract com-; vowels and h attract co-; everything else keeps con-.
A trick to remember it
Con-/com- = together, with. It generates hundreds of Spanish cognates: connect/conectar, compare/comparar, compete/competir, confirm/confirmar, communicate/comunicar, cooperate/cooperar. If the Spanish word starts with "con-" or "com-," the English usually does too.
Exercise 1 · Form the word
Exercise 2 · Pick the right one
Which form of the prefix is used in "compare"?
The prefix con-/com- means "together" or "with": connect, combine, cooperate, communicate, compare. In Spanish it usually maps to con-/com-.
The prefix con-/com- is pronounced /kɒn/ /kəm/. For example, "connect".
"nect" becomes "connect". It is a typical example of the con-/com- prefix.
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