Keeping it very simple, you could create a table of words and a relationship table for synonyms. You could consider adding a restriction like WordID1 < WordID2
to prevent repeating pairs of words (e.g, (1,2) and (2,1)).
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…