Arabic Dictionaries — الألفاظ

Arabic Almanac – Hans Wehr 4th ed. This page features several dictionaries in several languages: Lane’s Lexicon, LL Suplement, Lisan al-Arab, Steingass, Hava, Dict. and Glos of Quran by Penrice, Vocab of Quran by A.A. Nadwi, Dict. of Quran by M.G. Farid, Verbal Idoms of Quran, Kazimirski (French), Marbawi (Malay/Jawi), al Munawwir (Indonesian), Qamoos al-Waheed (Urdu), Mufradaat Alfaaz al-Quran (Urdu), Mukhtaar as-Sahih, al-Munjid (Urdu), Lughaat al-Quran (Urdu), Alfaaz Istilihaat al-Quran (Urdu), Qaamoos Alfaaz al Qur’an (Urdu), …
The website provides searchable high-resolution scans of the dictionaries. Most notably, one can search all of the listed dictionaries at once. Search is available in Arabic script as well as in transcription.

Almaany – Arabic support for identification of wordforms. This website allows searching for any form of an Arabic word one might encounter and lists what word these might be deducted from.