(geology) period
(dated) a kind of bench or couch
(dialectal) muntjac

kỉ hà
adj

(art, drawing, of shapes) geometric, as in rectangular, square, triangular, circular, etc.
(art, drawing, of lines) straight

kỉ luật

kỉ luật
noun

discipline

kỉ lục
noun

a record (most extreme known value of some achievement)

kỉ niệm

kỉ niệm
noun

memory, memories (good, bad, childhood memories, etc.)
souvenir, keepsake

verb

to commemorate, to celebrate

kỉ niệm chương

kỉ niệm chương
noun

commemorative award, memorial badge

kỉ vật
noun

souvenir, object owned to remind one of something