as-spun filament	filament spun and solidified without drawing & annealing
birefringence	measure of molecular orientation in polymers
bobbin (spool)	plastic or cardboard tube on which filaments are wound
die (nozzle)	orifice to eject a polymer solution or melt as coherent stream
die swell	relaxation and expansion of a polymer stream leaving the die
draw-down ratio (DDR)	ratio between die exit velocity and take-up velocity
draw ratio (DR)	ratio between speeds of take-up godet and winder
filament	continuous fiber, typically spun as multiple filaments
fully drawn yarn (FDY)	highly oriented filament(s) melt-spun with integrated drawing
glass-transition temperature (Tg)	temperature where an amorphous material’s state changes from hard to viscous
godet (roller, galette)	revolving cylinder for heating and drawing of filaments
hopper (funnel)	tapered chamber to hold and dispense feed material (polymer granulate, chips)
low oriented yarn (LOY)	filament(s) melt-spun at low speed to be post-processed by drawing and texturizing
melting temperature (Tm)	temperature where a crystalline material’s state changes from solid to liquid
necking	stress-induced, abrupt decrease in filament cross-sectional area, relevant for molecular orientation and crystallization
partially oriented yarn (POY)	partially oriented filament(s) to be post-processed by drawing & texturizing
spin finish	liquid applied to reduce electrostatic effects and facilitate processing of filaments
spinneret	equipment comprising multiple of dies to form filaments from a polymer solution or melt
staple fibers	filaments cut or torn into short fibers for yarn spinning or nonwoven production
texturizing	thermo-mechanical process to impart crimp and bulkiness to man-made filaments (draw textured yarn, DTY)
yarn count (titer)	linear density (mass per unit length) of fibers or yarns, with unit “tex” in the SI system (1 tex = 1 mg/m)
Abbreviations
COP	cyclo olefin polymer
HDPE	high-density polyethylene
LCP	liquid-crystal polymer
LDPE	low-density polyethylene
P3HB	poly-3-hydroxybutyrate
P4HB	poly-4-hydroxybutyrate
PA 6	polyamide 6
PA 6.6	polyamide 6.6
PAC	polyacetylene
PANI	polyaniline
PBAT	polybutylene adipate terephthalate
PBT	polybutylene terephthalate
PC	polycarbonate
PCL	polycaprolactone
PEDOT:PSS	poly(3,4-ethylenedioxithiophene) polystyrene sulfonate
PEE	poly(ether ester)
PEEK	polyetheretherketone
PEF	polyethylene furanoate
PEI	polyetherimide
PEN	polyethylene naphthalate
PET	polyethylene terephthalate
PF	polyfluorene
PGA	polyglycolide
PHA	polyhydroxyalkanoate
PHBH	polyhydroxybutyrate-co-hydroxyhexanoate
PHBV	polyhydroxybutyrate-co-hydroxyvalerate
PLA	polylactic acid
PMMA	polymethylmethacrylate
PP	polypropylene
PPP	poly(p-phenylene)
PPS	polyphenylene sulfide
PPV	poly(p-phenylene vinylene)
PPy	polypyrrole
PS	polystyrene
PTFE	polytetrafluoroethylene
PTh	polythiophene
PTT	polytrimethylene terephthalate
PU	polyurethane
PVDF	polyvinylidene fluoride
PVF	polyvinyl fluoride
TPO	thermoplastic polyolefin elastomer
TPU	thermoplastic polyurethane
UHMWPE	ultra-high molecular weight polyethylene