not to be relied up on (adjective) fly-by-night: unreliable and shady
Sinonime: menage a trois, ternary, ternion, third, triad, trichotomy, trilogy, trinity, trio, tripartition, triplet, triplets, triplex, triplicate, triplication, triplicity, triumvirate, trivium, troika
Antonime: dependable,
reliable,
reputable,
responsible,
trustworthy