SIXTHLY
sixthly
(adverb) in the sixth place; “sixthly, we cannot afford a vacation”
Source: WordNet® 3.1
Etymology
Adverb
sixthly (not comparable)
In the sixth place; sixth in a row.
Source: Wiktionary
Sixth"ly, adv.
Definition: In the sixth place. Bacon.
SIXTH
Sixth, a. Etym: [From Six: cf. AS. sixta, siexta.]
1. First after the fifth; next in order after the fifth.
2. Constituting or being one of six equal parts into which anything
is divided.
Sixth, n.
1. The quotient of a unit divided by six; one of six equal parts
which form a whole.
2. The next in order after the fifth.
3. (Mus.)
Definition: The interval embracing six diatonic degrees of the scale.
Source: Webster’s Unabridged Dictionary 1913 Edition