I.conj. [apocop. from si-ne], an adversative conditional particle, if however, if on the contrary, but if (good prose).
I. With a preceding si, nisi, quando, dum.
A. After si.
1. In gen.: “si domi sum, foris est animus: sin foris sum, animus domi est,” Plaut. Merc. 3, 4, 2; cf. id. ib. 3, 4, 7: hunc mihi timorem eripe: si est verus, ne opprimar; “sin falsus, ut, etc.,” Cic. Cat. 1, 7, 18 fin.: “si optimates ... sin populus, etc.,” id. Rep. 1, 42, 65: “quos si boni oppresserunt ... sin audaces,” id. ib. 1, 44, 68; “1, 37, 58: si nostri oblitus es ... sin aestivorum timor te debilitat,” id. Fam. 7, 14, 1: “qui si improbasset ... sin' probasset, etc.,” Caes. B. C. 1, 32: “si sine vi velint rapta tradere, redderent ... Sin aliter sient animati, etc.,” Plaut. Am. 1, 1, 54: “sin aliter es,” id. Trin. 1, 2, 9; Ter. Ad. 3, 5, 5; “and simply sin aliter, with a verb understood,” but if not, in the contrary case, Ter. Phorm. 1, 2, 66; Cic. Caecin. 24, 69; id. Fam. 11, 14, 3; Quint. 8, 6, 74 al.: “sin secus,” Plaut. Cas. 2, 6, 25: “accusator illum ... defendet, si poterit: sin minus poterit, negabit,” Cic. Inv. 2, 29, 88; “so simply sin minus,” id. Att. 9, 15, 1; id. Q. Fr. 2, 8, 2. —
2. In the epistolary style also, ellipt., sin (for sin aliter or sin minus): “si pares aeque inter se, quiescendum: sin, latius manabit,” Cic. Att. 16, 13, b, 2.—
3. Strengthened,
(α).
By autem: “si malus est ... sin autem frugi'st, etc.,” Plaut. Pers. 4, 1, 6; cf.: “id si ita est, etc. ... sin autem illa veriora,” Cic. Lael. 4, 14; Ter. Hec. 4, 1, 44; 5, 2, 14; Cic. Rosc. Am. 49, 142; id. Att. 3, 8, 6 and 7; Just. 16, 4, 14; 31, 5, 7 al.; cf.: “si sunt viri boni, me adjuvant ... sin autem minus idonei, me non laedunt,” Cic. Caecin. 1, 3; so id. Div. in Caecil. 11, 34; and in epistolary style, ellipti.: si vir esse volet, praeclara συνοδία: sin autem erimus nos, qui solemus id. Att. 10, 7, 2.—So freq. in Vulg.: “si est tibi intellectus, responde proximo: sin autem, sit manus tua super os tutum,” Vulg. Ecclus. 5, 14; 29, 8; id. Luc. 10, 6; id. Apoc. 2, 5.—
(β).
Less freq. by vero: si sit ovis matura ... sin vero feta, Col. 7, 3, 11.—*
B. After nisi: “nisi molestum est, nomen dare vobis volo Comoediaï: sin odio est—dicam tamen,” Plaut. Poen. prol. 51.—*
C. After quando: “quando abiit rete pessum, adducit lineam: sin jecit recte, etc.,” Plaut. Truc. 1, 1, 16 (Speng. si injecit).—*
D. After dum: “dum illi agunt suam rem agunt, ceteri cleptae: sin vident quempiam se adservare, obludunt,” Plaut. Truc. 1, 2, 10.—
II. Without a preceding si, nisi, etc. (where the foregoing particle is usu. clearly implied by the context).
A. In gen.: “qui ero servire servos postulat, etc. ... Sin dormitat, ita dormitet, ut, etc.,” Plaut. Aul. 4, 1, 5; cf. Cic. Rep. 3, 3, 6: Pae. Ne me attrecta. So. Sin te amo? Plaut. Pers. 2, 2, 45; cf. id. Ps. 1, 3, 22; id. Mil. 4, 8, 27: “primum danda opera est, ne quā amicorum discidia fiant: sin tale aliquid evenerit, ut, etc.,” Cic. Lael. 21, 78; cf. id. Off. 2, 21, 74: “adhuc nostri nulli fuerunt: sin quando exstiterint, etc.,” id. de Or. 3, 24, 95: “orat ac postulat, rem publicam suscipiant. Sin timore defugiant, etc.,” Caes. B. C. 1, 32; Nep. Ages. 1, 3: “haec ut fiant, deos quaeso, ut vobis decet. Sin aliter animus voster est, etc.,” Ter. Ad. 3, 4, 46.—
B. In epistolary style, ellipt.: “ego, ut constitui, adero: atque utinam tu quoque eodem die! Sin quid—multa enim—utique postridie,” Cic. Att. 13, 22, 4.—
C. Strengthened,
1. By autem: “summi puerorum amores saepe unā cum praetextā togā ponerentur: sin autem ad adulescentiam perduxissent, etc.,” Cic. Lael. 10, 34; 21, 77; id. Rep. 1, 6, 11; 2, 39, 66; id. Off. 1, 34, 123; id. Tusc. 3, 9, 19; id. Rosc. Am. 47, 137; Caes. B. G. 5, 35 al.—
