Lewis & Short

2. al-lĕgo (adl-), ēgi, ectum, 3, v. a., to select for one’s self, to choose (qs. ad se legere; like adimere, = ad se emere); to admit by election, to elect to a thing, or into (a corporation; in the class. per. generally only in the histt.): Druidibus praeest unus … hoc mortuo, si sunt plures pares, suffragio Druidum adlegitur, * Caes. B. G. 6, 13 Herz. (Dinter here omits adlegitur): augures de plebe, Liv. 10, 6: octo praetoribus adlecti duo, Vell. 2, 89: aliquem in sui custodiam, Suet. Aug. 49; so, in senatum, id. Claud. 24: inter patricios, id. Vit. 1: in clerum, Hier. adv. Jov. 1, n. 34 al.
Poet.: adlegi caelo, Sen. Agam. 804.
Hence, al-lectus (adl-), a, um, P. a. Subst.,

  1. A. A member chosen into any corporation (collegium): collegae, qui unā lecti, et qui in eorum locum suppositi, sublecti; additi Adlecti, Varr. L. L. 6, § 66 Müll.
  2. B. Those who were added to the Senate from the equestrian order, on account of the small number of the Senators, were called adlecti, acc. to Paul. ex Fest. p. 7 Müll.; cf. Suet. Caes. 41; id. Vesp. 9.