Conceptáculum, conceptáculi, n. g. pen. cor. Plin. Any hollowe thing apt to hold or receiue.Conceptiuæ feriæ Festo dicuntur.Holy dayes yearely kept at a certaine time.
Lewis and Short: Latin dictionary
conceptācŭlum, i, n. [concipio], that which receives something, a receptacle (post-Aug. and rare). I. Prop., Plin. 2, 45, 44, 115: sanguinis, Gell. 18, 10, 9; Front. Aquaed. 22 al.— II.Trop.: superbia aliubi conceptaculum, sed hic (sc. in superciliis) sedem habet, Plin. 11, 37, 51, 138.