-comonoid Grouplike in a -monoid In a -comonoid , the comultiplication can almost never be the diagonal map, since this is not linear. It can however act diagonally on a subset of elements. A grouplike of is a nonzero element such that . #m/def/ralg/hopf The set of all grouplikes in is denoted . #state/develop | #lang/en | #SemBr