Velarization is a secondary articulation on consonants that references the back of the tongue's closeness to the velum. Velarized consonants like English's dark /l/ ([ɫ]), are produced with flatter tongue bodies as the back of the tongue approaches the soft palate. In the Celtic languages, velarization is also known as broadening and is distinct from slenderization (i.e. attenuation). The contrast is marked overtly in the Gaelic writing system; broad consonants are adjacent to one of the broad orthographic vowels <a, o, u>, while slender consonants are always adjacent to <i, e>.
In Gaelic, velarization is sometimes used as a morphological cue in Noun Declension and is part of a four way phonemic contrast in sonorants.
The link below takes you away from the Gaelic Wiki to Wikipedia. Since wikipedia pages can be edited by anyone, they often contain inaccurate information. So be careful!
- Lamb, William (2003) Scottish Gaelic. 2nd edition. Munich: Lingcom Europa
- Ladefoged, D. (2010) A Course in Phonetics. 6th Edition. Wadsworth Publishing.