Synonyms for Erectile (same or very similar meaning)
WordNet sense 1 (upright in position or posture):
erect, upright, vertical
WordNet sense 2 (filled with vascular sinuses and capable of becoming distended and rigid as the result of being filled with blood):
cavernous
WordNet sense 3 (able or tending to expand or characterized by expansion):
expansive
From the ODE community, based on WordNet
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