undertime /ˌʌn.dəɹˈtaɪ̯m/verb 2/ˈʌn.dəɹˌtaɪ̯m/ noun 2forms 3 verb2 •To measure wrongly, so that it seems to take less time than actually required. •To underexpose. undertime /ˈʌn.dəɹˌtaɪ̯m/ noun2 •(informal) The time spent at a workplace doing non-work activities. •(no longer used) The later part of the day; afternoon; undertide.He, comming home at undertime, there found / The fayrest creature, that he euer saw, / Sitting beside his mother on the ground; / The sight whereof did greatly him adaw. — 1590 formsundertimed · undertiming · undertimes