Mouillé is a term describing a palatal

Palatal consonant

Palatal consonants are consonants articulated with the body of the tongue raised against the hard palate...

 or palatalized

Palatalization

In linguistics, palatalization , also palatization, may refer to two different processes by which a sound, usually a consonant, comes to be produced with the tongue in a position in the mouth near the palate....

 consonant, particularly l or n.

Mouillé consonants

	l mouillé	n mouillé
French French language French is a Romance language spoken as a first language in France, the Romandy region in Switzerland, Wallonia and Brussels in Belgium, Monaco, the regions of Quebec and Acadia in Canada, and by various communities elsewhere. Second-language speakers of French are distributed throughout many parts...	(i)ll	(i)gn
Italian Italian language Italian is a Romance language spoken mainly in Europe: Italy, Switzerland, San Marino, Vatican City, by minorities in Malta, Monaco, Croatia, Slovenia, France, Libya, Eritrea, and Somalia, and by immigrant communities in the Americas and Australia...	gl	gn
Spanish Spanish language Spanish , also known as Castilian , is a Romance language in the Ibero-Romance group that evolved from several languages and dialects in central-northern Iberia around the 9th century and gradually spread with the expansion of the Kingdom of Castile into central and southern Iberia during the...	ll	ñ
Portuguese Portuguese language Portuguese is a Romance language that arose in the medieval Kingdom of Galicia, nowadays Galicia and Northern Portugal. The southern part of the Kingdom of Galicia became independent as the County of Portugal in 1095...	lh	nh

Occurrence

L mouillé has a variety of origins in the Romance languages. In this table, letters that represent or used to represent palatal l (ʎ) are bolded. In French, /ʎ/ merged with /j/ in pronunciation in the 18th century; in many dialects of Spanish, /ʎ/ has merged or is merging with /ʝ/.

Latin	"better"	"ear"	"horse" !! "key" !! "moon"
Italian	migliore	orecchio	cavallo	chiave	luna
French	meilleur	oreille	cheval	clef	lune
Portuguese	melhor	orelha	cavalo	chave	lua
Catalan	millor	orella	cavall	clau	lluna
Spanish	mejor	oreja	caballo	llave	luna