cotizar - to quote prices, to prorate, to distribute proportionally

cristianizar - to christianize

crujir - to creak, to grate, to crunch

cuchichear - to whisper, to gossip

currar - to work

cursar - to study, to send, to process

colarse, (ue) - to slip

convertirse - (ie), to change

chirriar - creak

cartearse - correspond

conmutar - commute

conturbar - disquiet, harass, unsettle

correlacionar - correlate