Longpress does show it. The text at the top is exactly the same as on desktop.
But I don’t think this is that helpful. What does it help you to know that 
is explained as eyes? This is rather the name than the meaning of the emoji. When someone reacts to your post with eyes, that could mean “I’ll take a look.” However, Emojipedia states:
Sometimes used to indicate ‘pervy eyes’ to indicate approval of an attractive photo posted online; or ‘shifty eyes’ to convey a deceitful act.
How do we know what the person who reacted really meant? It depends on the context. I don’t think showing the name in the UX would help to understand the meaning.