Easton's Bible Dictionary (1897)
Mentioned in the list of unclean birds (Lev. 11:18; Deut. 14:16), is sometimes met with in the Jordan and the Sea of Galilee.
Smith's Bible Dictionary (1863)
(Heb. tinshemeth), thus rendered by the Authorized Version in (Leviticus 11:18; 14:16) where it occurs in the list of unclean birds Rut either of the renderings “porphyrio” (purple water-hen) and “ibis” is more probable. Neither of these birds occurs elsewhere in the catalogue; both would be familiar to residents in Egypt, and the original seems to point to some water-fowl. The purple water-hen is allied to our corn-crake and water-hen, and is the largest and most beautiful of the family Rallidae .
It frequents marshes and the sedge by the banks of rivers in all the countries bordering on the Mediterranean and is abundant in lower Egypt.
Hastings' Dictionary of the Bible (1898)
SWAN. This bird is mentioned only in Lev 11:18; Deut 14:16, and there as unclean. The swan is very rare in the Levant, while there seems to be no reason why it should not be eaten. It is possible that the sacred ibis, once abundant in Egypt may be meant, or the purple gallinule. Either of these birds might naturally be forbidden as food, from its unclean diet, and the former, also, as connected with idolatry.
Schaff's Bible Dictionary
SWAN. This bird is mentioned only in Lev 11:18; Deut 14:16, and there as unclean. The swan is very rare in the Levant, while there seems to be no reason why it should not be eaten. It is possible that the sacred ibis, once abundant in Egypt may be meant, or the purple gallinule. Either of these birds might naturally be forbidden as food, from its unclean diet, and the former, also, as connected with idolatry. SWEAR Ps 15:4. See Oath.