As a noun terms
is .
As an adjective unmatchless is
(proscribed) unmatched; matchless.
terms
English
Noun
(head)
Statistics
*
----
unmatchless
English
Adjective
(-)
(proscribed) unmatched; matchless
References
* Google Books: [https://www.google.co.uk/search?tbs=bks%3A1&tbo=1&q=%22unmatchless%22&btnG=Search+Books]