Boyd’s Bible Dictionary:
(bitter). Naomi so called herself (Ruth 1:20).
Concise Bible Dictionary:
An appellation which signifies “bitter,” assumed by Naomi because of her sorrow (Ruth 1:20).
Strong’s Dictionary of Hebrew Words:
Meaning:
for 4751 feminine; bitter; Mara, a symbolic name of Naomi
Jackson’s Dictionary of Scripture Proper Names:
he was arrogant: bitterness
Potts’ Bible Proper Names:
Bitter:―a symbolical name of Naomi, Ruth 1:20. {Amarus}