電磁波 (Tiān-chû-pho) (electromagnetic wave) 是 (sī)有 (ū)電場 (tiān-tiûⁿ) (electric field) 邯 (ham)磁場 (chû-tiûⁿ) (magnetic field) 佇 (tī)空間 (khong-kan)傳播 (thoân-pò)的 (ê)1種 (chióng)波 (pho)。電磁波是電磁 (tiān-chû)輻射 (hok-siā)現象 (hiān-siōng)的一 (chi̍t)面 (bīn); 咱 (lán)爿疏 (pêng-sò͘)講 (kóng)的光 (kng)，窮實 (khêng-si̍t)就 (tō)是電磁波。電場甘 (ham)磁場成做 (chiâⁿ-chò)90° 咧 (teh)幌動 (hàiⁿ-tāng) (oscillate)，佮 (kap)傳播的方向 (hong-hiòng)嘛 (mā)攏 (lóng)相 (sio)徛直 (khiā-ti̍t)。
電磁波有能量 (lêng-liōng)甘運動量 (ūn-tōng-liōng)，會當 (ē-tàng)傳 (thoân)予 (hō͘)拄著 (tú--tio̍h)的物質 (bu̍t-chit)。
