Entry 1 sense Webster, 1913 Experimenter /ĭk-spĕr'-əm-ĕnˌ-tẽr/ · Ex·per·i·men·ter · IPA /ɪkˈspɛɹ.ə.mɛn.tɚ/ 01 n. One who makes experiments; one skilled in experiments. 1. One who makes experiments; one skilled in experiments.