Download of SynMap 1.2.4 for Mac was available from the developer's website when we last checked. We cannot confirm if there is a free download of this app available. The application lies within Education Tools, more precisely Languages. The actual developer of this software for Mac is Sergejs Melderis. We recommend checking the downloaded files with any free antivirus.
From the developer:
SynMap is a visual dictionary that lets you discover word meanings and its relations with other words in an intuitive and interactive way. When searching for a word, SynMap creates a map of word meanings and provides you with all its synonyms and other related words.
You may want to check out more software for Mac, such as collatinus, English-Italian Dictionary '08 or Japanese-English Dictionary, which might be similar to SynMap.