1) steadfastness, constancy, endurance
1a) in the NT the characteristic of a man who is not swerved from his deliberate purpose and his loyalty to faith and piety by even the greatest trials and sufferings
1b) patiently, and steadfastly
2) a patient, steadfast waiting for
3) a patient enduring, sustaining, perseverance
Part of Speech: noun feminine
Citing in TDNT: 4:581, 581
From G5278; cheerful (or hopeful) endurance, constancy: - enduring, patience, patient continuance (waiting).
These two sites give similar information, with the definition from several dictionaries and statistics on the use of the word.
Perseus Digital Library
University of Chicago's Logion lexicon
Thayer's dictionary plus other information.
From this site's dictionary (in Italian)
Click on the first column to search for that word as a form of the root ὑπομονή; click on the second column to search for that grammatical form of the root ὑπομονή; click on the third column to search for that word and grammatical form; click on the total to search for the root ὑπομονή.