Phoebe Sarah Hertha Ayrton (1854 nî 4 goe̍h 28 ji̍t – 1923 nî 8 goe̍h 23 ji̍t) sī Eng-kok ê ki-su, sò͘-ha̍k-ka, bu̍t-lí-ka, kiam hoat-bêng-ka. I pat in-ūi tī tiān-hô͘ (electric arc) kap soa chham chúi ê éng chò ián-kiù tit tio̍h Ông-ka Ha̍k-hōe ê Hughes Medal siúⁿ.