When we say "beaver away," it means to work diligently or tirelessly. To express the same idea using different words, we can say "to toil away," "to labor tirelessly," "to work fervently," or "to strive continuously." Another synonym for this phrase is "to grind away," indicating a long and arduous grind or prolonged effort. Additionally, we can use "to hammer away," "to plug away," or "to soldier on" to reflect the persistent and focused approach to work. Whatever the synonym, the underlying message is the same - toil with determination and unwavering commitment.