IPA: /ˈfɪnlaɪk/
KK: /ˈfɪnˌlaɪk/
Having a shape or appearance similar to a fin.
The fish had finlike structures that helped it swim.
Finlike → It is formed from "fin" (from Old English "finn", meaning a limb or appendage of a fish) and "-like" (meaning resembling or having the characteristics of). The word "finlike" describes something that resembles or has the characteristics of a fin.
Think of a 'fin' as a fish's limb, and remember that 'finlike' means something that resembles a fin.