a.
1.
Sour, tart, rough, acrid.
2.
Morose, surly, testy, touchy, cross, growling, snarling, snappish, cantankerous, waspish, petulant, peevish, churlish, harsh, acrimonious, caustic, captious, censorious, splenetic, out of sorts, ill-tempered.
3.
Difficult, perplexing, trying, unmanageable, tough, intractable, hard to deal with.