ˌʌndə(ɹ)ˈvælju make too low an estimate of he underestimated the work that went into the renovation Don't underestimate the danger of such a raft trip on this river make a deliberately low estimate The construction company wanted the contract badly and lowballed assign too low a value to Don't underestimate the value of this heirloom-you may sell it at a good price an estimation that is too low; an estimate that is less than the true or actual value