Cottonseed oil reimagined: From invisible commodity to engineered lipid system in a fibre-dominated crop

Cotton ( Gossypium spp.) is cultivated primarily for fibre, and cottonseed oil remains under-optimized despite cottonseed being produced in comparable or greater mass than lint. This review re-examines cottonseed oil as a designable lipid trait, focusing on oil content, fatty acid composition, functional lipid properties, and the source–sink equilibrium between seed oil accumulation and fibre development. We synthesize current understanding of carbon allocation, seed development, triacylglycerol (TAG) assembly, and fibre–oil relationships, highlighting the need to improve oil content without compromising lint yield or fibre quality. Advances in RNA interference, natural mutant discovery, and CRISPR/Cas-mediated editing show that cottonseed oil composition can be extensively reprogrammed, particularly through high-oleic oil with improved oxidative stability and limited effects on fibre traits. Further diversification through modified palmitic and stearic acid levels, nutritional ω-3/ω-6 fatty acids, and industrial fatty acids such as vernolic acid expands the potential applications of cottonseed oil beyond conventional edible use. Improved understanding of cyclopropenoid fatty acid (CPFA) biosynthesis and TAG assembly also creates opportunities to reduce antinutritional CPFAs, increase oil value, and optimize oil accumulation. We argue that cottonseed oil improvement should be integrated with fibre-focused breeding, production systems, and value-chain development, repositioning cottonseed oil as a feedstock for industrial lubricants, coatings, bio-based materials and specialty lipid manufacture while retaining fibre performance.