postsigno

A genuine seam, and a lovely one. Most of the long words in this band are international borrowings pretending to be compounds. This one is the real thing, and it takes apart perfectly: post at rank 43, after or behind, plus signo at 472, a sign. A postsigno is an after-sign - the mark a thing leaves once it has passed. You could meet the word for the first time in a sentence and read it correctly without a dictionary, which is the whole promise of compounding delivered in one word. Read it from the right, as that article says: the last root is the head, so a postsigno is a kind of signo, and post- only says which kind.

Against spuro. Spuro at 1,579 is the borrowed word, German Spur, and it is the one you want for a track you can follow: a line of prints across a field, a scent, a trail. Spuro implies direction. Postsigno does not: it is what remains, the residue, the mark that something was here. A hunter follows the spuroj of a deer; a war leaves postsignoj on a town. The English pair trace and track splits the same way, and in practice spuro is much the commoner word, so learn postsigno for the abstract sense where English would say "traces of" or "vestiges of".

The family. Postsigni is to leave marks behind; senpostsigne means without a trace, and it is one of the more satisfying adverbs in the language - la ŝipo malaperis senpostsigne. Note that post- is a live prefix all over the vocabulary: postmorta, posttagmezo, postvivi (to survive, literally to after-live). Once you have it, every one of those reads itself.