Read the dictionary definition of earlier. All definitions for this word.
1. (comparative and superlative of `early') more early than; most early
1. a fashion popular in earlier times
2. his earlier work reflects the influence of his teacher
3. Verdi's earliest and most raucous opera
2. earlier in time; previously
1. I had known her before
2. as I said before
3. he called me the day before but your call had come even earlier
4. her parents had died four years earlier
5. I mentioned that problem earlier
3. before now
1. why didn't you tell me in the first place?
4. comparatives of `soon' or `early'
1. Come a little sooner, if you can
2. came earlier than I expected