Now they that died
muwth  (mooth)
causatively, to kill
in the plague
maggephah  (mag-gay-faw')
a pestilence; by analogy, defeat -- (be) plague(-d), slaughter, stroke.
were fourteen
'arba`  (ar-bah')
four -- four.
`asar  (aw-sawr')
ten (only in combination), i.e. -teen; also (ordinal) -teenth -- (eigh-, fif-, four-, nine-, seven-, six-, thir-)teen(-th), + eleven(-th), + sixscore thousand, + twelve(-th).
'eleph  (eh'-lef)
hence (the ox's head being the first letter of the alphabet, and this eventually used as a numeral) a thousand -- thousand.
and seven
sheba`  (sheh'-bah)
a primitive cardinal number; seven (as the sacred full one); also (adverbially) seven times; by implication, a week; by extension, an indefinite number
me'ah  (may-aw')
a primitive numeral; a hundred; also as a multiplicative and a fraction -- hundred(-fold), -th), + sixscore.
beside them that died
muwth  (mooth)
causatively, to kill
about the matter
dabar  (daw-baw')
a word; by implication, a matter (as spoken of) or thing; adverbially, a cause
of Korah
Qorach  (ko'rakh)
ice; Korach, the name of two Edomites and three Israelites -- Korah.