Word 684: התפתחות (bl)

More than one possibility opens before us:

-A feminine-type plural, ending in ות, preceded by article.

-A noun PS-t having prefix הת and suffix ות.

Only the second fits here: look at ptr PS-t0445.

Dictionaries have indeed the feminine noun הִתְפַּתְּחוּת, development, evolution.

Pronunciation: hitpatHut

ul