animal horns
犄 centers on animal horns, specifically the hard, pointed growths on the heads of cattle and similar animals.
犄 combines 牜 (cow) with 奇, which likely contributes the sound and may relate to the idea of something odd or singular, possibly referring to the distinctive shape of horns.
The left side 牜 is a cow, and the right side 奇 looks like a strange, pointed shape. Imagine a cow with unusually large, strange horns: 犄 means animal horns.
For イ, picture an eagle (イーグル) swooping down to grab a cow by its horns: eagle -> イ, and the cow's horns are the target.