polytene adjective 1noun 1forms 3 adjective1 •Having very large chromosomes with many chromatids (arms).When this was done, it could be shown that the production of polytene chromosomes is not uniform for all chromosomes of a single nucleus, ie, some chromosomes are more polytene than others, […] — 1957 noun1 •A very large chromosome with many chromatids (arms); a chromosome exhibiting polytenyUnlike normal chromosomes, polytenes are visible in a microscope even when cell division is not taking place. — 2002 formspolytenes · more polytene · most polytene