| doltish |
| down-to-earth(adjective, tough, rational, straightforward, sober) |
| draggy(adjective, dull, flat, lifeless, dreary) |
| driveling(adjective, dull, flat, stupid, ordinary) |
| dry-as-dust |
| dull as dishwater(expression, adjective, idiom, dull, stupid) |
| earthy(adjective, tough, rational, straightforward, sober) |
| emotionless(adjective, tough, rational, straightforward, sober) |
| factual(adjective, simple, tough, plain, ordinary) |
| fearful(moderate, cautious, conventional, timid, traditional) |
| feasible(adjective, tough, rational, straightforward, sober) |
| firm(moderate, cautious, conventional, timid, traditional) |
| flavorless(adjective, excite) |
| fogyish(moderate, cautious, conventional, timid, traditional) |
| forthright |
| frank |
| fuddy-duddy(moderate, cautious, conventional, timid, traditional) |
| garden-variety |
| guarded(moderate, cautious, conventional, timid, traditional) |
| hard-boiled(adjective, tough, rational, straightforward, sober) |