Search for "guitar" as an instrument (main MB page or relationship editor).
Top hit, with score 100, is "banjitar". "guitar" (an exact match for the query!) only scores 97.

There are similar cases - "perc" up to "percussio" give "body/foot/other percussion" as 100-score hits; "percussion" and "tuned percussion" lag behind (and further the longer the query becomes: 93 for "perc", 89 for "percussio").
For "percussion", "percussion" becomes the sole 100-score hit, and the other percussion entries (which I would expect to be relatively close behind due to a full word of their name being matched) get scores between 64 and 68.