candor / candid
(n) quality of being honest or straightforward / (adj) straightforward or blunt
catalyst
(n) something that causes an important event to happen
ceaseless
(adj) continuous or uninterrupting
coincide
(v) to happen simultaneously
complacent
(adj) contented to a fault by oneself or one’s actions
confluence
(n) flowing together
contention
(n) uneven argument, dispute or competition
contrite
(adj) feeling or expressing pain or sorrow for sins or offenses
concur
(v) to be in agreement
copious
(adj) large in quantity, abundant