Con- with, together, along

 Concede –– to admit as true or valid after first denying or resisting it, acknowledge grudgingly or hesitantly (concede a point) Con + Cede (go, grant)

Concession – an act or instance of conceding, granting, or yielding; a thing conceded or granted

 2. Concentric –having a center in common (as in concentric circles), con + centricus, center 

3. conciliatory –intended or likely to placate or pacify; intended to gain goodwill or favor or to reduce hostility                                   

4. Concur – to be of the same opinion; to agree. con + currere, to run

5. Concurrent – existing, happening, or done at the same time; occurring or existing together (currere)

6. Condescend –to show feelings of superiority; to be patronizing; to do something in a haughty way, as though it is below one’s dignity or level of importance - con + descendere, to descend CONDESCENDING

7. Conducive – making a certain situation or outcome likely or possible; con + ducere, to lead- (think also of CONDUCT, like conducting electricity)

8.  conduit – a means for conducting something, particularly a tube, pipe, or passageway for fluid (a channel for conveying water or other fluid) (but often used metaphorically) con + ducere

9. confidant. One to whom secrets are entrusted; one to whom a person CONFIDES (NOT CONFIDENT)– con + fidere, trust

10.  contemporaneous adj. Living, occurring, or existing at the same time. Con + tempor

11.  contemptible adj. Worthy of scorn or disdain; despicable – con (int.) + temnere, ‘despise’ 

12.  contemptuous adj. showing contempt; scornful (basically the inverse of contemptible) 

13.  contiguous adj. sharing a common border or boundary (con + tangere, to touch)                      

14.  contingent adj. subject to chance; occurring or existing only if (certain circumstances) are the case; dependent on

15.  conflagration n. A great fire (as of many buildings, a forest, etc); often used metaphorically. Con + flagrare, to blaze

16.   confluence n. The place where streams meet à an act or process of merging, of coming together. - fluere, to flow