maithe1. 1. f. (gs. ~).Goodness, good. (In phrase) Ar mhaithe le, for the good of, for the sake of. Bheith ar mhaithe le duine, to have s.o.’s interest at heart. Ar mhaithe leis féin a bhí sé, he was thinking of his own good. Ar mhaithe lena shláinte, for the sake of his health. Ar mhaithe leat féin ná déan é, for your own sake don’t do it. 2. gsf. & npl. of maith2.