noun
desk edition; desk dictionary
Refers to a dictionary or reference work sized for desk use, larger than a pocket edition but smaller than a full library edition.
この国語辞典の机上版は、収録語数が多くて便利だ。
The desk edition of this Japanese dictionary has many entries and is convenient.
ポケット版 is a pocket edition, smaller and more portable than a 机上版.
Compound of 机上 (on the desk) and 版 (edition).