From flat + -ling.
flatling (comparative more flatling, superlative most flatling)
- Flatly, plainly.
- In a flat position.
- With the flat side (e.g. of a weapon).
- 1596, Edmund Spenser, The Faerie Queene, V.5:
- Tho with her sword on him she flatling strooke, / In signe of true subjection to her powre […].