Wiktionary
n. (context neologism English) The favourable association of gay and lesbian people and/or gay rights with a nationalist ideology.
Wikipedia
Homonationalism describes the favourable association between a nationalist ideology and LGBTI people or their rights.
The term was originally proposed by the researcher in gender studies Jasbir K. Puar to refer to the processes by which some powers line up with the claims of the LGBTI community in order to justify racist and xenophobic positions, especially against Islam, basing them on prejudices that migrant people are necessarily homophobic and that western society is entirely egalitarian. Thus, sexual diversity and LGBT rights are used to sustain political stances against immigration, being increasingly common among far-right parties.
The main critiques of this phenomenon focus on the partial and sectarian use of the LGBT movement to further ends based in intolerance, ignoring the homophobia and lack of real equality in Western society as a whole. This false idea of equality is usually symbolically represented by the access to equal marriage, heteronormalizing the relations between the people of the LGBTI community and favouring chauvinistic positions towards the Western country and suspicions towards people coming from those countries that have not legalized any kind of recognition of same-gender couples or that still criminalize homosexuality, often associating those stances with Muslims.