Why is the ninth month called September?
late 14c., "flax prepared for spinning," also "refuse of flax used as kindling," somehow from the source of Old English lin "flax" (see linen), perhaps from or by influence of Middle French linette "grain of flax," diminutive of lin "flax," from Latin linum "flax, linen;" Klein suggests from Latin linteum "linen cloth," neuter of adjective linteus. Later "flax refuse used as tinder or for dressing wounds" (c.1400). Still used for "flax" in Scotland in Burns' time. Applied in American English to stray cotton fluff.