| fairweather(adjective, unreliable, insecure, treacherous, incalculable) |
| fallible(adjective, unreliable, insecure, treacherous, incalculable) |
| false-principled |
| faltering(uncertain, hesitant, dubious, unsure) |
| fanciful |
| fitful(adjective, changeable, indecisive, inconsistent) |
| fixed(adjective, dishonest, immoral, rotten, untrustworthy) |
| flighty(adjective, changeable, indecisive, inconsistent) |
| flustered(uncertain, hesitant, dubious, unsure) |
| foresworn(adjective, false, fickle, untrue, untrustworthy) |
| forsworn(adjective, mean, bad, base, false) |
| foul(adjective, mean, base, dishonest, immoral) |
| glib(lying, misleading) |
| gone to the dogs(expression, adjective, idiom, dishonest, immoral) |
| guileful(adjective, false, dishonest, cunning, deceitful) |
| hesitant(uncertain, dubious, unsure) |
| hesitating(uncertain, hesitant, dubious, unsure) |
| hopeless(adjective, unreliable, insecure, treacherous, incalculable) |
| iffy(adjective, unreliable, insecure, treacherous, incalculable) |
| in a quandary(expression, idiom, uncertain, hesitant, dubious) |