† trideˈcennary, a. Obs. rare—1.
[An irregular formation from L. tredecim thirteen.]
Intended to mean: Of or pertaining to the number thirteen.
(By the form, it ought to mean ‘Of thirteen years’.)
| 1783 Robertson Hist. Amer. (ed. 4) III. 385 Computed..first by what he calls a tridecennary progression of days from one to thirteen,..and then by a septenary progression of days from one to seven, making in all twenty. |