Synonyms for Unilateral (same or very similar meaning)
WordNet sense 1 (tracing descent from either the paternal or the maternal line only):
unilateralist
WordNet sense 2 (in a straight unbroken line of descent from parent to child):
direct, lineal
WordNet sense 3 (involving only one part or side):
one-sided
From the ODE community, based on WordNet
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