Enchantment, sorcery.
a1225 [see
SIGALDER
n.]. 13.. K. Alis. 7015 (W.), Quede and harme he wil me
spye,..Gef he wot of this sygaldrye [Laud trigoldrye] That this trowes [=
trees] kan lye. ?a1500 Chester Pl., Crucifixion (Shaks. Soc.) II. 69 Burye hym wher thy wil be, But look thou make no sigaldry To
raise him up agayne.
Sigalder:
Obs. rare.
A charm or incantation.
c1000 Saxon Leechd. I. 388
Sy
e-ealdor ic begale, sie ~yrd ic me wee . a1225
Ancr. R. 208 Sigaldren
[v.r. sigaldrie], & false teolunges, leuunge on ore & of swefnes,
& alle
wichchecreftes.
Hence 
sigalder v., to enchant,
bewitch. Obs.
1303 R. BRUNNE Handl. Synne 503
ere was a wycche, and made a bagge, A
bely of le
yr ,..She sygaldryd so ys bagge bely at hyt 
ede and soke mennys ky.