I before E, except after C
In English words that contain the letters I and E together, the I tends to come before the E (ie), except in cases when the two are preceded by the letter C, in which case the E comes before the I (cei).
character
The third letter of the English alphabet, called cee and written in the Latin script.
num
The third numeral symbol of the English alphabet, called cee and written in the Latin script.
adv
Alternative form of c..