The 25-year-old has joined initially until January and is available for Saturday's cinch League 1 match with Dumbarton.
McDaid began his career with Morton and had spells with Partick Thistle and Ayr United before joining Dundee in 2019.
He had been due to go back to to Thistle on loan earlier this year when the season was suspended due to Covid, but on its resumption, back at Dundee, he helped the Dens Parkers gain promotion to the top flight.
Bairns head coach Paul Sheerin told the club website: "Declan is an exciting player with loads of pace who is never afraid take on his man and will always look to get forward.
Most Popular
-
1
Nicky Hogarth: Former Graeme High pupil signs for Falkirk on loan from Premier League newcomers Nottingham Forest
-
2
'First class attitude' the key to Falkirk's 3-1 victory over Peterhead, says boss
-
3
Falkirk 3-1 Peterhead: Hosts dominate to pick up first win of the league campaign
-
4
Average league attendances for all 42 SPFL clubs in 2019/20 season
-
5
Will Vaulks: Former Falkirk favourite completes shock third tier move
"His signing boosts our attacking strength and gives us another option in an extremely important area of the pitch, and I look forward to working with him in the coming months.”