It is specifically a dictionary of Scots, or Lallans, which some scholars consider merely a dialect of English and others a distinct language rooted in Old English.
( It ( ( ( is specifically ) ( ( ( ( a dictionary ) ( of Scots ) ) ( , ( or ( Lallans , ) ) ) ) ( which ( ( some scholars ) ( consider ( ( ( merely ( a dialect ) ) ( of ( ( English and ) others ) ) ) ( ( a ( distinct language ) ) ( rooted ( in ( Old English ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (PRP It)) (VP (VBZ is) (ADVP (RB specifically)) (NP (NP (NP (DT a) (NN dictionary)) (PP (IN of) (NP (NNP Scots)))) (PRN (, ,) (CC or) (NP (NNP Lallans)) (, ,)) (SBAR (WHNP (WDT which)) (S (NP (DT some) (NNS scholars)) (VP (VBP consider) (S (NP (NP (RB merely) (DT a) (NN dialect)) (PP (IN of) (NP (NP (NNP English)) (CC and) (NP (NNS others))))) (NP (NP (DT a) (JJ distinct) (NN language)) (VP (VBN rooted) (PP (IN in) (NP (NNP Old) (NNP English))))))))))) (. .)))
Scots/Lapllans are seen by scholars as an English dialect rather than a different language. 
( Scots/Lapllans ( ( are ( seen ( by ( scholars ( as ( ( ( an ( English dialect ) ) ( rather than ) ) ( a ( different language ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNS Scots/Lapllans)) (VP (VBP are) (VP (VBN seen) (PP (IN by) (NP (NP (NNS scholars)) (PP (IN as) (NP (NP (DT an) (JJ English) (NN dialect)) (CONJP (RB rather) (IN than)) (NP (DT a) (JJ different) (NN language)))))))) (. .)))