网络与数据通信 有线网络 释文 non-acknowledgement, NAK 否定应答
- Orchid Blooms in Spring Sunshine
- orchid garden
- Orchid Journal
- Orchid-Land Selection of Ci Poems of the Ming Dynasty
- Orchid of the Valley
- Orchid Painting Technique
- Orchid Pavilion in Shaoxing
- Orchid，Rock by Ma Shouzhen
- orchiocatabasis
- orchitis
- ORCID
- OR curve
- Orcus
- ORD
- Ordained
- ordaitopsida
- ORDBMS
- ordeal
- orde disorder transformation
- order
- orderability
- orderable
- orderable field
- orderable group
- orderable semigroup