Indeed they are two different things but I can understand the OP's confusion. Of the hotels I use most frequently Hilton Sydney, Adelaide, Brisbane and Cairns all have executive lounges and have 'lounge" listed as an amenity. No mention of the word executive. Hilton Parmelia Perth and Doubletree Cairns have no executive lounge and none on their amenity list. As Melbourne Doubletree has one listed but has no executive lounge you could describe this all as confusing. Clear as mud? I usually go by whether the hotel has executive rooms but this is not always 100% reliable.