1) Downplay 2) Express with restraint 3) Inform 4) Lowball 5) Make little of 6) Minimise 7) Minimize 8) Opposite of exaggerate 9) Represent with restraint 10) Sandbag in poker 11) Set forth with restraint 12) Speak with restraint 13) To minimise or downplay 1) Downplay 2) Fudge 3) Minimise 4) Trivialise 5) Trivialize 
• (v. t.) To state or represent less strongly than may be done truthfully.
[v] - represent as less significant or important
to state or represent less strongly or strikingly than the facts would bear out; set forth in restrained, moderate, or weak terms: The casualty lists understate the extent of the disaster.