Worthy of being congratulated; deserving praise or good wishes for an achievement.
From congratulate (Latin congratulari 'to wish well with others,' con- 'with' + gratulari 'to be pleased') + -able (suffix meaning 'capable or worthy of'). A modern formation in English.
This is a rare word—most people just say 'congratulations' instead of calling something 'congratulable'—but it describes achievements that are genuinely worthy of celebration, not just polite nods.
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