Yarn that's a part of Chasing rainbows(7) I*G*E*N
Think the other letters are ok though the E could be an A if I have got hold of the wrong half of the pun for the other clue
Ingrain | Define Ingrain at Dictionary.com
Ingrain definition, to implant or fix deeply and firmly, as in the nature or mind. ... made of dyed yarn or of fibre that is dyed before being spun into yarn