From The Collaborative International Dictionary of English v.0.48:
adit \ad"it\ ([a^]d"[i^]t), n. [L. aditus, fr. adire, aditum, to
go to; ad + ire to go.]
1. An entrance or passage. Specifically: The nearly
horizontal opening by which a mine is entered, or by which
water and ores are carried away; -- called also drift
and tunnel.
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2. Admission; approach; access. [R.]
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Yourself and yours shall have
Free adit. --Tennyson.
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