Eucharist and Communion mean the same thing. Those who say it doesn't just want to fight.
Eucharist is also used in place of the word 'Mass' - lots and lots of priests leave off 'celebration of the/this' [Eucharist] and say, "welcome to this Eucharist" or something similar.
'Eucharist' is used as a pronoun: 'Eucharistic people' 'Eucharistic gathering' and 'Eucharistic sharing' 'Eucharistic community' 'Eucharistic celebration'.
We pray that our common baptism and the action of the Holy Spirit in this Eucharist will draw us closer to one another and begin to dispel the sad divisions which separate us.
Which sounds like 'this Eucharist' is Holy Communion when in fact, 'this Eucharist' must mean the Mass otherwise it must mean that the Eucharist (Body and Blood) will begin to dispel division and separation and so everyone must be invited to partake, which isn't true.
Sinkspur, most Catholics get very confused by wording like that. The above sounds like the word Eucharist means the Mass and yet the Mass is also referred to as 'the celebration of the Eucharist' and then it goes on to say 'Eucharistic sharing' is forbidden. The word Communion is used in a narrow way and that is not confusing at all but the word 'Eucharist' is used to mean many things.
As a fairly well [in]formed Catholic, I can read between 'bishopspeak' lines, but I pity the fool ;-) who isn't used to being a catholspeakwordjuggler.