From The Collaborative International Dictionary of English v.0.48 [gcide]:
Lammas \Lam"mas\, n. [AS. hl[=a]mmesse, hl[=a]fm[ae]sse, loaf
mass, bread feast, or feast of first fruits; hl[=a]f loaf +
m[ae]sse mass. See Loaf, and Mass religious service.]
The first day of August; -- called also Lammas day, and
Lammastide.
[1913 Webster] Lammergeier
Lammergeir
From WordNet (r) 3.0 (2006) [wn]:
Lammas
n 1: commemorates Saint Peter's miraculous deliverance from
prison; a quarter day in Scotland; a harvest festival in
England [syn: Lammas, Lammas Day, August 1]