outside the ablaut system; in fact, the common gradation ā : ə necessarily implies the ablaut of a, as ē : ə does that of e; see vi.
Many indications point to a being an Ar. survival of a pre-Aryan sole vowel a, which ordinarily split up in Ar. into e and o. It is preserved in child-language because this is conservative; thus while Ar. *tata gives W. tad ‘father’, in W. child-speech it remains as táda. In the ordinary language a stands side by side with e/o, or occurs where we should expect e/o, in the following cases: 1. initially; 2. before *ə̯ or i̯; 3. before gutturals. Thus 1. at‑, ati‑: et‑, eti- pref. and adv. ‘beyond, and, but’ § 222 i (3); O. W. anu, Ir. ainm ‘name’ < *án(ə)mn̥, Armen. anun ‘name’: Gk. ὄνομα < *ónəmn̥, √onō‑/anō‑.—2. The ending of the neut. pl. nom.-acc. is *‑ə; now the neut. pl. of o/e-stems is ‑ā from *‑aə, where *‑a- represents the stem vowel instead of ‑o- (or ‑e‑); similarly the fem. of o/e-stems is formed with ‑ā- for *‑aə‑; but i̯o/i̯e-stems have beside ‑iā- < *‑iaə- the fem. form ‑i̯ē- < *‑i̯eə‑. Cf. also ā : ō ix below. In the dat. sg. of cons. stems both ‑ai and ‑ei occur, as Gk. infin. suff. ‑μεναι: Osc. diúveí, patereí, Solmsen KZ. xliv 161 ff.
In the positions indicated, a has R- and L-grades. Thus, 1. Initially: F *am- in Gk. ἀμφί, Lat. ambi‑: R *m̥- in Ir. imb, imm, W. am, ym‑, Skr. abhí-taḥ (a- < *m̥‑) ‘on both sides’; F *ar- in W. arth, Gk. ἄρκτος: R *r̥- in Lat. ursus, Skr. ŕ̥kṣah § 98 i (2); F *ag̑- in Lat. ago, Gk. ἄγω: L *āg- in Lat. amb-āges.—2. Before ə̯ or i̯: F *ā (< *aə): R *ə, see vi; F *ai- in Gk. αἴθω, Ir. aed ‘fire’, W. aelwyd: R *i- in Skr. idh-má‑s ‘firewood’. For the fem. of i̯o/i̯e-stems there is beside ‑i̯ā- and ‑i̯ē- a form ‑ī‑; this may be explained thus: RF *ii̯aə, *ii̯eə give ii̯ā, ii̯ē: RR *ii̯ə > ī, vii (2). Cf. vii (5).
3. Before gutturals : √ak̑‑: oq- ‘sharp, rugged’, as Gk. ὄκρις, ὀξύς, Lat. ocris, W. ochr: Gk. ἄκρος, Lat. acus, W. (h)agr ‘ugly’;—√dek̑/g̑h- ‘to seem good, acceptable; to apprehend, teach’; e in Lat. decus, decet, Ir. dech, deg, ‘best’: o in Lat. doceo, Gk. δοκέω, δόγμα: a in Gk. διδάσκω (< *διδαδσκω), διδάχη, W. da ‘good’ < *dag‑, Gaul. Dago‑, Ir. dag- ‘good’.
vi. (1) The long vowels ē, ō, ā had R- and V-grades; ē had also the F°-grade ō. The R-grade of each is ə. Before a vowel ə regularly disappears, giving the V-grade, as in Skr. dá-d-ati ‘they give’, where ‑d- is the V-grade of √dō‑. It also occurs before consonants, as in Skr. da-d-máḥ ‘we give’ beside Gk. δί-δο-μεν; but the disappearance of ə between consonants is believed to be due to analogy or elision after the Ar. period. It is however lost in syllables not initial or final in Germ., Balt.-Slav., Armenian, Iranian; Meillet, Dial. 63.
ə appears to come from a guttural spirant resembling ᵹ (§ 110 ii (2)), which played the same part as the sonants, so that the ablaut series of ē is parallel to that of ei̯ or er, the F-grade ē being for *eə̯; thus V (ə non-syllabic, lost) ; R ə (syllabic); F ē for *eə̯; F° ō for *oə̯; corresponding to V i̯ (non-syllabic); R i (syllabic); F ei̯, F° oi̯. This explains why ə is the R-grade of all the long vowels.
