Diphthongs

Diphthongs are sequences of two vowels joined together to act as one, long vowel sequence. There are approximately 9 diphthongs in Gaelic. We can divide these into two classes: (A) those which are spelled using two vowels, and (B) those which are spelled using a combination of vowels and consonants.

Type A

[iə] from ia
[iəR]	iarr	demand!
[kʲiəL]	ciall	sense (n.)
[Lʲiə]	liath	grey (adj.)
[biəɣ]	biadh	food
[fiəɣ]	fiadh	deer
[iəRɪ]	iarraidh	wanting

[uə] from ua
[fuər]	fuar	cold
[guəL]	gual	coal
[kLuəs]	cluas	ear
[sguəb]	sguab	brush!
[tuəɣ]	tuagh	axe (n.)
[duəʃ]	duais	prize
[buəj]	buaidh	impact (n.)

[ia] from eu Note: not all eu vowels are pronounced as diphthongs, e.g. Seumas where eu is pronounced as a long é [eː] sound
[biaL]	beul	mouth
[kʲiad]	ceud	hundred
[fiar]	feur	grass
[gʲiar]	geur	sharp

Note: eum is usually pronounced as é [eː]
[Lʲeːm]	leum	jump!
[kʲeːm]	ceum	step (n.)
[beːm]	beum	stroke

Type B

These diphthongs occur before ll, nn, m and also before the fricatives bh, mh, gh, dh in which case those fricatives are often silent.

[ai] from ai
[kaiLʲ]	caill	lose!
[saiLʲ]	saill	salt!
[kaiNʲdʲ]	cainnt	speech
[ɣaiv]	dhaibh	to them
[taiʃə]	taibhse	ghost

[ei] from ei
[ʃeiNʲ]	seinn	sing!
[beiNʲ]	beinn	mountain

The first part of the diphthong does not exist in English. You can produce this sound by making an [o] and spreading your lips at the same time, as if you were grinning widely.

[ɤi] from ei, ai, oi
[mɤiLʲ]	moill	delay (n.)
[kɤiLʲdʲən]	coilltean	forests
[sɤiLʲʃɪç]	soillsich	enlighten!
[LɤiNʲ]	loinn	elegance
[brɤim]	broim	fart (n.)
[grʲɤim]	greim	grip (n.)
[sɤidʲɛr]	saighdear	soldier
[mɤidʲan]	maighdean	maiden

Like the last diphthong, but the first part of this diphthong is like the unrounded form of [u]. Again, you can produce this sound by making an [u] and spreading your lips at the same time, as if you were grinning widely. NB: Some dialects pronounce this sound like [ɤ].

[ɯi] from ui, aoi
[krɯiNʲ]	cruinn	round
[drɯim]	druim	ridge
[sɯim]	suim	sum (n.)
[tɯiLʲ]	tuill	holes
[krɯiv]	craoibh	tree (dative)
[Nɯiv]	naoimh	saints
[Lɯij]	laoigh	calf (genitive)
[mrɯ͂ĩ]	mnaoi	wife (dative)

[au] from a, ea
[kaum]	cam	crooked
[kauL]	call	loss
[bauL]	ball	member
[ann]	ann	in him
[RauN]	rann	verse
[bauN]	bann	band
[Lãũmbə]	lampa	lamp
[sãũrəɣ]	samhradh	summer
[kʲauN]	ceann	head
[pjauN]	peann	pen (n.)
[tʲauN]	teann	tight
[gʲauL]	geall	bet!
[gʲãũrəɣ]	geamhradh	winter

[ɔu] from o
[tɔum]	tom	hillock
[kɔum]	com	torso
[Lɔum]	lom	bare (adj.)
[dɔuN]	donn	brown
[fɔuN]	fonn	melody
[bɔuN]	bonn	base
[sɔuN]	sonn	hero
[tɔuL]	toll	hole
[pɔuL]	poll	mud

Summary chart

Summary chart of Scottish Gaelic diphthongs:
TYPE (A)	[iə]	ia
	[uə]	ua
	[ia]	eu
TYPE (B)	[ai]	aill, ainn, aibh
	[ei]	einn
	[ɤi]	oill, oinn, oim
	[ɯi]	uinn, uim, uill, aoi(bh/mh/gh)
	[au]	(e)am, (e)ann, (e)all, (e)amh
	[ɔu]	onn, om, oll