α. Old English on under, Old English onunder, Middle English on-vnder, Middle English one vnder.
β. late Old English–Middle English 1700s– anunder, Middle English an onder, Middle English anondyr, Middle English an under, Middle English an-under, Middle English an-vnder, Middle English anvnder, Middle English an-vndyr, Middle English (1800s– regional) anonder; English regional 1800s an-under, 1800s unnonder (northern), 1800s– anuner; Scottish pre-1700 anonder, 1700s–1800s anoner; Irish English 1800s annundher, 1800s– anundher, 1900s– anondher, 1900s– anondther, 1900s– anunner, 1800s anunder.
γ. early Middle English en under; English regional 1800s– en onder, 1800s– in-onder, 1800s– in under, 1800s– in-under, 1800s– inunder; Scottish (now Shetland) pre-1700 1800s inonder, 2000s– innunder; Irish English 1800s innundher, 1800s– inundher, 1900s– inunder.