köken: Taken out of the clarifying compound Schwiegermutter (“mother-in-law”), itself from Schwieger (“mother-in-law”), from Old High German swigar (“mother-in-law”), from Proto-West Germanic *swegru, from Proto-Germanic *swegrō, from Proto-Indo-European *sweḱrúh₂. Related to Schwager (“brother-in-law”), Schwäher (“father-in-law”). Cognate with Alemannic German schwëcher-.
köken: Borrowed from German schwieger- (“-in-law”), extracted from Schwiegermutter (“mother-in-law”), older Schwieger, from Proto-Germanic *swegrō, cognate with Old English sweġer. The word goes back to Proto-Indo-European *sweḱrúh₂ (“mother-in-law”), hence Latin socrus), Ancient Greek ἑκύρα (hekúra), Sanskrit श्वश्रूः (śvaśrū́ḥ). It is further related to *swéḱuros (“father-in-law”) (German Schwäher,…
aile: brawd yng nghyfraith, cydfrawd yng nghyfraith, chwaer yng nghyfraith, mab yng nghyfraith, mam yng nghyfraith, merch yng nghyfraith, modryb yng nghyfraith, plant yng nghyfraith, rhieni yng nghyfraith, tad yng nghyfraith
köken: From French beau- (used to indicate a male relation by marriage, as in beau-père, beau-frère, or beau-fils), used in Esperanto regardless of gender.