ad-ven-ti-tious [ad-vuh n-tish-uh s]
1. associated with something by chance rather than as an integral part; extrinsic.
2. Botany, Zoology. appearing in an abnormal or unusual position or place, as a root.
Origin: 1595-1605; < Latin adventicius literally, coming from without, external, equivalent to ad- ad- + ven- (stem of venire to come) + -t (us) past participle suffix + -icius -itious
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