Ianua
（θύρα). A door; denoting more especially the first entrance to the house through which one entered from the street. This door was also called by the Romans anticum, and by the Greeks θύρα αὐλεία, αὐλία, etc. The back-door was termed posticum, postica, and posticula; in Greek, παράθυρος, dim. παραθύριον, and κηπαία (θύρα). The doors of the inner apartments were called ostia, and in Greek μέσαυλοι or μέταυλοι, etc. A secret door was styled pseudothyrum (ψευδόθυρον).The complete doorway consisted of the four indispensable parts—threshold (limen, βηλός, ὀυδὸς ὁδός), lintel (iugumentum, limen superum), and jambs (postes, σταθμοί). Vitruvius speaks of the jambs as antepagmenta. For the hinges, see Cardo. The door itself was called foris, valva, and in Greek σανίς, κλισίας, θύρετρον. It was regularly bivalve or double, and hence spoken of in the plural.
The threshold was an object of reverence, and it was thought unlucky to tread on it with the left foot. On this account the steps leading into a temple were of an uneven number, because the worshipper, after placing his right foot on the bottom step, would then place the same foot on the threshold also (Vitruv. iii. 4). The doors of Greek houses regularly opened inward, and of Roman houses always so, with the single exception of the house of M. Valerius Publicola (Pliny , Pliny H. N. xxxvi. 112), who was exempted from the usual rule as a special honour.
As early as Homer we find mention of a contrivance for bolting or unbolting a door from the outside,
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| Temple Door. (Roman bas-relief.) |
By night the front door of the house was further secured by means of a wooden and sometimes an iron bar (sera, repagula, μοχλός） placed across it, and inserted into sockets, on each side of the doorway. Hence it was necessary to remove the bar in order to open the door (reserare). Even chamber doors were secured in the same manner (Heliodor. vi. 9); and here also, in case of need, the bar was employed as a further security in addition to the two bolts (Eurip. Orest. 1551, 1571; Iph. Aul. 345; Androm. 951). Where, as in the case of tyrants, midnight assassination was especially dreaded, we read of a bedchamber secured with a portcullis (Plut. Arat. 26). To fasten the door with the bolt was ianuae pessulum obdere, with the bar, ianuam obserare. At Athens a jealous husband sometimes even sealed the door of the women's apartment (Thesm. 427; Menand. Incert. 1, 11). The door of a bedchamber was occasionally covered with a curtain (velum). See Domus.