धातु - dhātu

W. D. Whitney, The roots



√āñch, ‘tear’

Pres. [1.] āñchati c.
Deriv. āñchana c.
Found only in the suśruta, and doubtless artificial.
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āp, ‘obtain’

Present. [5.] āpnóti etc. av.+  , āpnute e.
Perf. ā́pa āpitha etc. v.+ , āpiré āpāná rv.
Aor. 1. āpi b.+ — 2. ā́pat etc. v.+  (apeyam av. ) — 3. āpipan śb.+ (āpīpipat bau. ) — 4. āpsīs e.+ )
Fut. 1. āpsyati b.+ , -te b.r. ; 2. āptā b. 
Verb. āptá v.+ ; ā́ptum b.+ , āptvā́ b.+ ; āpya b.+
Sec. Conj.: Pass. āpyáte etc. b.+ Desid. ī́psati etc. av.+ , īpsate etc. b.e. (āipsīt etc. b. ) — Caus., āpayati etc. b.+ , -te etc. e. (āpipayiṣet śb. )
Deriv.:

-āpa b. + -āpanīya s. + -āptṛ c. īpsā e. +
-āpaka e.+ āpaneya u.1  ā́pnāna? rv.s. -īpsin u.
-āpin u.+ āpí v.+ -āpayitavya u.c. -īpsu s.+
āpyá av.+ ā́pti av.+ āpayitṛ u. āpipayiṣu e.
āpana v.+ āptavya u.+    


To a more original form of the root (āp is perhaps ā + ap) doubtelss belong also:

ápas v.  apás v.b. ápnas, apna- rv. -apta (? án-) rv.
       


BR. regard apás at rv.iii.6.7 as a verb-form from this simpler root.
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ār, ‘praise’ (?)

Pres. [4.] ā́ryanti rv.2
Verb. āritá rv.
Is perhaps a form of ā + √ṛ, ‘resort to, have recourse to’; ā́ryanti in both occurrences is accented as if it contained a preposition.
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ās, ‘sit’

Pres. [2.] ā́ste etc. (ā́sīna) v.+ , āsti e. ; [1.] āsati -te etc. e.+ , [4.] āsyati -te etc. e.
Perf. āsā́ṁ cakre etc. b.+ , āsā́ṁ cakāra e. 
Aor. [5.] āsiṣṭa etc. b.s. 
Fut. 1. āsiṣyate etc. b.+ , -yáti ts. [— 2. āsitā.]
Verb. āsitá b.+ , āsitum b.+ , āstum k.  āsitvā́ b.s.  ; -āsya c. </span>
Sec. Conj.: Pass. āsyate e. + [— Desid. āsisiṣa--.] — Caus. āsayati b.
Deriv.:

-āsá v. b.  -āsya u. -āsanīya c. -āsti c.
-āsā u. āsyā e.+  āsitavyá b. +.  
-āsaka e. āsana av. -āsitṛ e.