mighteth

From might + -eth.

mighteth

1. (nonstandard, pseudo-archaic, hypercorrect) (archaic) third-person singular simple present indicative of may.

• This verb form is nonstandard; the historical third-person singular past tense of verbs was always identical to the first-person singular, unlike the present tense. Contrastively, second-person singular "mightest" is historically correct.