D defs.my
Entry 1 sense Webster, 1913

Father-in-law

/fäth'-ẽr-ĭn-lôˌ/ · Fa·ther-in-law · IPA /ˈfɑːðəɹɪnˌlɔː/
01 n. The father of one's husband or wife; -- correlative to son-in-law and daughter-in-law.
pl. Fathers-in-law
  1. 1.
    The father of one's husband or wife; -- correlative to son-in-law and daughter-in-law.