Perhaps Proto-Mongolic *kata- ( “ to harden, to dry out ” ) + -aa .
kataa
salt
Borrowed from Arabic قَطَعَ ( qaṭaʕa ) .
-kataa (infinitive kukataa )
to refuse , deny , object , renounce
18th century , Abdallah bin Ali bin Nasir, Al-Inkishafi [1] , translation from R. Allen (1946 ) “Inkishafi—a translation from the Swahili”, in African Studies , volume 5, number 4, →DOI , pages 243–249 , stanza 11 :هُنِلِزِ نَمِ كَلِ بَيْنِ ، لِوَاپُ نَسُرَ نِسِ كَتَيْ Hunelezi nami kali baini, liwapo na-sura nisi katae . Can't you tell it me plainly that I may admit it?
Conjugation of -kataa
Positive present
-na kataa
Subjunctive
-katae
Negative
-katai
Imperative singular
kataa
Infinitives
Imperatives
Tensed forms
Habitual
hukataa
Positive past
positive subject concord + -li kataa
Negative past
negative subject concord + -ku kataa
Positive present (positive subject concord + -na kataa)
Singular
Plural
1st person
ni nakataa/na kataa
tu nakataa
2nd person
u nakataa
m nakataa
3rd person
m-wa(I/II)
a nakataa
wa nakataa
other classes
positive subject concord + -na kataa
Negative present (negative subject concord + -katai )
Singular
Plural
1st person
si katai
hatu katai
2nd person
hu katai
ham katai
3rd person
m-wa(I/II)
ha katai
hawa katai
other classes
negative subject concord + -katai
Positive future
positive subject concord + -ta kataa
Negative future
negative subject concord + -ta kataa
Positive subjunctive (positive subject concord + -katae )
Singular
Plural
1st person
ni katae
tu katae
2nd person
u katae
m katae
3rd person
m-wa(I/II)
a katae
wa katae
other classes
positive subject concord + -katae
Negative subjunctive
positive subject concord + -si katae
Positive present conditional
positive subject concord + -nge kataa
Negative present conditional
positive subject concord + -singe kataa
Positive past conditional
positive subject concord + -ngali kataa
Negative past conditional
positive subject concord + -singali kataa
Perfect
positive subject concord + -me kataa
"Already"
positive subject concord + -mesha kataa
"Not yet"
negative subject concord + -ja kataa
"If/When"
positive subject concord + -ki kataa
"If not"
positive subject concord + -sipo kataa
Consecutive
kakataa / positive subject concord + -ka kataa
Consecutive subjunctive
positive subject concord + -ka katae
Some forms not commonly seen in modern Standard Swahili are absent from the table. See Appendix:Swahili verbs for more information.