With the exception of the final Aristophanic quotation and a slight modification in a phrase (see n.8 below), this entry is taken almost entirely from Photius, Lexicon zeta58. See also Pollux 10.177; Hesychius zeta184; etc.
[1] As in zeta 179 and kappa 542, the definition is taken from a military "tactics" text. (As in zeta 179, see: Onomasticon Tacticon 26; Aelian, Tactica 7.)
[2] A definition widely attested in different lexica, from where Photius may have excerpted it. Herodian, De prosodia catholica 3.1.140, has e)/sti de\ zugo\s kai\ ka/qedra tw=n e)resso/ntwn; 'the zugo/s is also the seat for rowers'; and in a scholion to Sophocles, Ajax 249 has 'zugo/s means three things: the plate of a balance, the seat, and the yoke of the animals'. See also, likewise, a scholion to Homer, Iliad 20.246: 'for zuga/ are the seats for rowers'.
[3] This is considered the main meaning of this term, and is attested in different lexica and grammars. See e.g. Apion, Fragmenta de glossis homericis 74.239 (the first of three definitions there). A scholion to Homer, Iliad 5.730, has '*zugo/s: what is put on the neck of horses', and a scholion (scholia recentiora) to Aristophanes, Clouds 745, has '*zugo/s is what oxen are submitted to, and by that they draw the chariot'.
[4] See already n.2.
[5] In Apion, Fragmenta de glossis homericis 74.239: '*zugos: ... Also in relation to the lyre'. A scholion (scholia vetera) to Homer, Iliad 187, has 'the cross-piece of the lyre where the kollaboi/ are placed; this is the name of the pegs to which the strings are fastened'.
[6] For zugo/s 'balance' and i)so/ths 'equality', see e.g. Gennadius Scholarius, Grammatica 2.441: 'balance means the law and the equality'.
[7] On Libra and Scorpio see e.g. Teucer Astrologus, De duodecim signis 7.204: sunh/nthke *zugo\s a)po\ tw=n tou= *sko/rpiou xhlw=n; 'Libra appears starting from the claws of Scorpio'.
[8] Slightly different from the original: kai\ h( zugotruta/nh: truta/nh de\ to\ sta/simon; 'and the zugotrutanê: trutanê is what measures the weight', which is clearer than in the Suda. The term zugotruta/nh is attested here and in Photius, the main source (see introductory note above). For the coincidence of zugo/s with truta/nh cf. tau 1105; Hesychius tau1570; and the scholia to Demosthenes 5.26: 'truta/nh is the whole balance [zugo/s], the scales are the plates where we put what is to be weighed'. In the scholia to Lycophron, Alexandra 270 we find a more detailed description of the part of the balance, and, according to that, the truta/nh could not mean, at least during a certain age, the whole balance but a part of it: 'Now ta/lanton is the flat, laminated part of the balance, where we place the things to be weighed, the truta/nh, which is also named staxa/nh, the entire rod of the balance on both sides of which there are the plates or scales. Properly speaking the truta/nh is the strap of the rod of the balance'. This is confirmed by Eustathius, Commentary on Homer's Iliad 1.301: 'properly speaking, the truta/nh is a part of the zugo/s… And the zugo/s itself takes its name from the part, upon which the already-mentioned pla/stigges hang'.
[9] This is a phrase that Photius could have taken from Hesychius zeta196: 'also the cross strap round the toes in the sandals', which has perhaps its origin in the scholia to Aristophanes, Lysistrata 417: 'zugo/s is the name of the cross strap that rounds women's sandals passing through toes'.
[10] Aristophanes, Lysistrata 417.