VERB (2)

1. reach the point where one should be after a delay;
- Example: "I caught up on my homework"

2. learn belatedly; find out about something after it happened;
- Example: "I'm trying to catch up with the latest developments in molecular biology"

WordNet (r) 3.0 (2006):

catch up
    v 1: reach the point where one should be after a delay; "I
         caught up on my homework"
    2: learn belatedly; find out about something after it happened;
       "I'm trying to catch up with the latest developments in
       molecular biology"

Moby Thesaurus II by Grady Ward, 1.0:

31 Moby Thesaurus words for "catch up":
   abduct, carry off, catch up with, come up to, come up with,
   ensnare, entangle, entrap, fascinate, gain on, gain upon, grip,
   hold, kidnap, lap, leave behind, leave standing, mesmerize,
   outpace, outrun, outsail, outstrip, overhaul, overtake, pass,
   shanghai, snare, spellbind, tangle, throttle, trap