| 释义 |
pre-operculum, præ-|priːəʊˈpɜːkjʊləm|
[f. præ, pre- A. 4 + operculum.]
1. Ichth. The foremost of the four bones forming the operculum in fishes.
1828Stark Elem. Nat. Hist. I. 454 Head scaly; operculum with spines, and the preoperculum with dentations. 1880Günther Fishes 80 The side of the skull, in front of the operculum, is covered by a large irregularly-shaped bone, held by some to be the præoperculum.
2. Bot. = operculum 2.
1864Webster, Preoperculum, Bot., the fore-lid or operculum in mosses. (Also in later Dicts.) |