gumption

The Japan Times Online Sept.27 の記事からの引用です。
‘Sea of Opportunity’ charts the history of immigrant Japanese fishermen in Hawaii
The common image of Japanese immigrants toiling in the sugarcane fields of Hawaii and -- through years of sheer gumption -- rising in the social of the island is well established.
"gumption" 意味は何でしょうか？　苦労または努力と推測できますが、苦労と努力では意味が違います。辞書で確認します。
・Oxford English Dictionary: Shrewd or spirited initiative and resourcefulness: she had the gumption to put her foot down and head Dan off from those crazy schemes
・Merriam-Webster's Online Dictionary: courage and confidence: It took a lot of gumption to speak up for yourself like that.
・Vocabulary.com: If you have gumption, you have guts. People with gumption are determined and full of courage — and common sense, too.
If you easily give up, and don't have a lot of confidence or smarts, then you are lacking in gumption. It takes gumption to get things done — especially difficult things. Someone who takes risks without being afraid has gumption. Having gumption is like having "chutzpah." We all could probably use more gumption. Like common sense, it isn't that common.
私の推測はハズレでした。根性とかやる気、積極性、進取の気性などの意味でした。