Some wrong Spanish etymologies

Some Coromines' Spanish etymologies (the ones found in the DRAE are generally nastier) enjoy a greater credit than they actually deserve.

For example, if we look at cerrar 'to close, shut' in his Breve diccionario etimológico de la lengua castellana, we can see he derives it from late Latin *serare < Latin sera 'bolt, lock', in spite that Spanish /c/ (in the Middle Ages a dental affricate [ts] and now an interdental fricative [θ]) can't come from Latin /s/. He denies elsewhere any relationship between this word and Catalan serrar, French serrer 'to tighten', although they fit both phonetically (as [ts] > [s] in these languages) and semantically (the meanings 'closed' and 'tight, dense' are related). The answer is all these words¹ are Pyrenaic (a Vasco-Caucasian substrate language) loanwords from the PNC root *=utɕE(rV) 'thick, fat'.

Another weird etymology is jara 'rockrose (Cistus)', a kind of bush common in the Iberian Peninsula which Coromines derives from Arabic ša^cra 'low bush', where [ʃ] /x/ regularly developed into [χ] /j/. Apparently, he ignores Basque zare 'basket' and (t)xara 'rockrose (wood)', a word of Pyrenaic origin for which Bengtson suggests an etymology from PNC *tʃ’ʃ’wɦeli (˜ tɕ’ɕ’,-ʕ-,-ɫ-) 'a k. of foliage tree'². The palatized form would have been borrowed into Spanish xara, then jara.

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¹ There's also Basque (Biscayan) zarri 'dense', zarra-tu 'dense; to close, shut'.
² Related to Paleo-Eurasian *tʃwalV 'willow', a root represented in Paleo-European *sal(i)k- 'willow' (Celtic *salik-, Latin salix, Germanic *salx-) and native IE *welik- 'willow' (Greek helíkē, English willow).

The magpie and the heron

There's a class of onomatopoeic roots *kVr- which designate several types of birds.

For example, Aragonese garza, Catalan garça, Italian gazza 'magpie' < *karkea is an Italoid loanword from PIE *ḱarhk-eh2- 'magpie' (Lithuanian šárka, Russian soróka)¹, akin to Turkic *KArga 'crow' and PNC *q’q’HVrVq’V 'a k. of bird (magpie; eagle-owl)'.

The homonymous Spanish garza 'heron'² is a loanword from Celtic *kor(x)sā 'heron, crane', probably through a Cantabrian intermediate *karsa. A similar root can be found in Latin ardea 'heron' < PIE *h1orhd-eh2- 'heron', akin to Turkic *Kordaj 'pelican; swan'.

Latin corvus 'raven' is a loanword from Afrasian *ɣurVb- 'crow, raven', and cornīx 'crow' is akin to Uralic *kOrnV 'raven'.
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¹ Probably also Celtic *kerkā 'hen'.
² In Spanish, 'magpie' is urraca.

Spears and poles

Basque langa 'enclosure, rustical door; bar, catch (on a door or window)'¹ is related to Occitan/Catalan tanca id.², with a sound shift *t- > l- in Proto-Basque.

This is an Italoid substrate loanword whose etymology is IE *tengh-s- 'pole' > Latin tēmō 'steering-wheel; spear (of a cart)' and Old English þīsl 'wagon-pole, shaft'³. This IE root is a -n- infixed variant of *(s)teg- 'pole, post' (English stake), which in turn is related to PNC *dwɨq’(w)V: 'log, stump'.

This Vasco-Caucasian root is found as a Vasconic loanword in Spanish taco, Catalan tac 'block of wood, wedge; wooden stick', French taquet (diminutive form) 'block of wood, wedge', as well as in Basque haga 'pole, stake'⁴. The Tyrrhenian variant is found in Spanish tocón (augmentative form), Portuguese tôco 'stump' and also in Catalan soca, French souche 'stump', Old French choque 'log' and Spanish zoquete (diminutive form) 'block of wood; dumb, stupid'⁵, with assibilation of the initial dental.
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¹ Mitxelena derives it from Romance *planka 'plank, board'.
² Coromines proposes a derivation from a hypothetical Sorotaptic verb *tankō- 'to close'.

³ See Mallory & Adams (2006), p. 249.
⁴ There's also non-standard Basque tako 'circular piece of wood' and taket 'stake, wedge; dump, stupid'.

⁵ Coromines considered this word to be an arabism. What a zoquete!

The fate of Proto-Basque *t-

Proto-Basque's consonant system had a tense/lax contrast rather than a voiceless/voiced one, so dental stops were *t: (tense) and *t (lax).

Initial *t- was apparently absent from Late PBsq., as d- is exceedingly rare in modern Basque outside of recent borrowings and verbal forms. Although Trask noticed this anomaly in Mitxelena's system, he didn't offer any explanation¹.

The key is found in borrowings like lanjer (< French danger) or lizifrina (< Romance disciplina)², where the original d- evolved into l-. This suggests EPBasq. *t- became Basque l-, as in these examples:

Basque langa 'enclosure, rustical door; bar, catch; crossbeam' ~ Catalan tanca < EPBsq. *tanka  (IE *teng^h-s- 'pole')

Basque lan(h)o, laino 'cloud, fog' ~ non-std Basque t(t)anka 'drop' < EPBsq. *tank:A (PNC *t’Hænk’o 'drop, spray')

It looks like Iberian t was actually realized like a dental affricate [t^s]³ which gave a lamino-alveolar sibilant [s] (Basque <z>)⁴ in loanwords from that language in Basque:

Basque zohi 'clod of earth; brick' < Iberian *tok:i but lohi 'mud', idoi 'pool, puddle; bog, marsh' < EPBsq. *(i-)tok:i (Starostin's PSC *[t]VQV́ 'dirty, clay')

EPBsq. *t:- gave Basque is h or zero, as in these examples:

Basque haga 'stake, pole' < EPBasq. *t:akA ~ non-standard tako 'block of wood, wedge' (PNC *dwɨq’(w)V: 'log, stump')

Basque -ar 'male', Aquitanian HAR- ~ non-std Basque *-tar 'man' < EPBasq. *t:ar: (PNC *dlʒiwlV 'man, male')
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¹ The History of Basque (1997), p.136.

² It's worth noticing these words are geographically restricted to a few dialects.
³ See his Economie des changements phonétiques (1955).
⁴ This sound shift is often quoted by Ibero-Basquists (defensors of a close relationship between Basque and Iberian) as being a native Basque one.