Synonyms for Ungenerous (same or very similar meaning)
WordNet sense 1 (lacking in magnanimity):
meanspirited
WordNet sense 2 ((used of persons or behavior) characterized by or indicative of lack of generosity):
mean, miserly
WordNet sense 3 (giving or spending with reluctance):
close
WordNet sense 4 (unwilling to spend):
stingy, stingy
From the ODE community, based on WordNet
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