Lesser Glyph of Infusion is a crafting component in The Witcher 3: Wild Hunt that is needed to craft lesser glyphs.
Crafting Requirements 
It can be crafted, found as random loot in monster nests, or purchased from the following merchants:
- All armorers except Zoltan Chivay
- All alchemists except Jonna in Rannvaig and the Freya Priestess on Hindarsfjall
- Armors merchant in Nilfgaardian Army Group 'Center' Camp
- Halfling merchant in Silverton
- Merchant in the boatyard south of Refugees' Camp
- Merchant at Coast of Wrecks
- Merchant in Ursten
- Merchant at the sawmill northeast of Rannvaig
- Scoia'tael merchant in the forest south of Novigrad
- Merchant in Mohrin Village
- Runewright at Upper Mill