Verbs based on root *tušt-
tъštati
3sg.prs tъštitъ (i-stem), 2/3sg.aor tъšta (a-stem)
Leskien class IV
ipf aspect
reflexive
arguments: sę, inf/sup, da + prs, na + acc, (kъ +) dat, o + loc
prefix variation: vъz-, po-, prě- (pf)
ESSJ (1007) and SJS show the lemma tъštati sę, giving i-stem presents and ptcp potъštavъ sę (Lk 19:5)
it could be a fientive, but LIV (642) mentions only adj. tъštъ ʹemptyʹ, itself likely based on a PIE sk-present (like skt. tucchyá-), so it is likely a denominal construction
Derksen (502) reconstructs *tus-sk-io-
Mikl. gives also aje-presents attested from 13th c. (distinguishing lemmas based on probably denominative pf tъštiti and ipf tъštati)
Examples in the corpus: potъštati tъštanie tъštja
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