Pliny writes of druids using sickles to cut mistletoe,
and there are curved swords (coined Falcata in the 19th century) from the pre-Roman Iberian peninsula.
Are there any references to druids actually using these curved swords? The timing and location seems plausible, but I've not found a direct reference other than those implied by games, like Dungeons & Dragons, where the druid character class (loosely based off of Celtic/Gallic historical druids) wield (rather anachronistically) scimitars
in what appears to be an effort to associate them with a curved sword.
This may be unanswerable since
"not one single artefact or image has been unearthed that can undoubtedly be connected with the ancient Druids." Hutton, Ronald (2009). Blood and Mistletoe: The History of the Druids in Britain. p. 23
I did find this, but I can't read Latin. It does however have the words, druid and machaera Hispana, the latter referred to in the article on the falcata.
Thanks to the helpful comment from @Comintern, the portion that mentions the curved sword comes back from google translate as
The reason that he was angry because he allowed himself the knowledge of the means of the old fabu- 1am and take away : * Do Thou, of course, are not the one . ' * We / I * Caesar, not to recognize me , for when this was done, I was a whole . Afterwards it belonged to me, the eye in the battle of Munda, 5 , torn out , and at the head of some bones . Nor helmet if seem to recognize that . Spain is divided saber / He forbade her performances Caesar and business fields in which viripotens the cause of strife and lawsuits had been a soldier in his favor.
and the portion that mentions druids
The Germans differ much from these usages, of safety. for 20 they have neither Druids to preside over those who the things of God , nor
But there is no clear correlation between the two, nor is the translation clear enough to provide any insight.
I also found this from the Deal Warrior find, but the sword is not curved, nor does it have the characteristic hilt of the Iberian curved sword.