Hence, the term isogloss , from iso - `same' + gloss `word,' to describe the line on a map where the terms are of equal distribution.
( Hence ( , ( ( the term ) ( ( ( ( isogloss , ) ( from ( ( iso - ) ( ` ( same ( ' + ) ) ) ) ) ) ( ( ( ( ( gloss ` ) word ) , ) ' ) ( to ( ( ( describe ( the line ) ) ( on ( a map ) ) ) ( where ( ( the terms ) ( are ( of ( equal distribution ) ) ) ) ) ) ) ) ) . ) ) ) )
(ROOT (S (ADVP (RB Hence)) (, ,) (NP (DT the) (NN term)) (VP (VBZ isogloss) (, ,) (PP (IN from) (NP (NP (NN iso)) (: -) (NP (`` `) (JJ same) ('' ') (NNS +)))) (VP (VB gloss) (`` `) (NP (NN word)) (, ,) ('' ') (S (VP (TO to) (VP (VB describe) (NP (DT the) (NN line)) (PP (IN on) (NP (DT a) (NN map))) (SBAR (WHADVP (WRB where)) (S (NP (DT the) (NNS terms)) (VP (VBP are) (PP (IN of) (NP (JJ equal) (NN distribution))))))))))) (. .)))
The word isogloss refers to the line on a Mao where terms are equally distributed. 
( ( The ( word isogloss ) ) ( ( ( refers ( to ( ( the line ) ( on ( a Mao ) ) ) ) ) ( where ( terms ( ( are equally ) distributed ) ) ) ) . ) )
(ROOT (S (NP (DT The) (NN word) (NNS isogloss)) (VP (VBZ refers) (PP (TO to) (NP (NP (DT the) (NN line)) (PP (IN on) (NP (DT a) (NNP Mao))))) (SBAR (WHADVP (WRB where)) (S (NP (NNS terms)) (VP (VBP are) (ADVP (RB equally)) (VP (VBN distributed)))))) (. .)))