Dictionaries
Hans Wehr, A Dictionary of Modern Written Arabic. [online] [other formats]
Hava, Arabic-English Dictionary. (medieval Arabic) [online] [other formats]
Lane, Arabic-English Lexicon. (based on medieval Arabic dictionaries) [online] [pdf, 8 vols.]
Steingass, Arabic-English Learner's Dictionary (1884). [online] [other formats]
Wortabet's Arabic-English Dictionary. [online] [other formats]
Ahmadnagari. Dustur al-'ulama'. Beirut: Dar al-kutub al-'ilmiyya, 2000. [online] [pdf zip download]
Dozy, Reinhart Pieter Anne. Supplément Aux Dictionnaires Arabes. 2 vols. Leyde,: E.J.Brill, 1881. Vol. 1 alif-sad [online]. Vol. 2 dad-ya' [online]
Kazamirski. Dictionnaire arabe-français. Vol. 1 alif - sad. [online] [other formats]. Vol. 2 dad - ya'. [online] [other formats]
Al-Tahānawī, Kashshāf iṣtilāḥāt al-funūn (Arabic dictionary of technical terms) [1996 ed 2 vols in 1] [1899 ed pdf and other formats through ṣād only] محمد علي بن علي التهانوي. كشاف اصطلاحات الفنون
Ṣalībā, Jamīl. Al-Muʿjam al-falsafī bi-al-alfāẓ al-ʿarabiyya... Vol. 1 alif-dad [pdf]. Vol. 2 ta'-ya' [pdf] صليبا، جميل. المعجم الفلسفي بالألفاظ العربية
ejtaal.net/aa/ search by Arabic root and view results from Wehr, Lane, Lisān al-ʿArab, Kazamirski and others on one web page
baheth.info/ Lisān al-ʿarab and other classical Arabic dictionaries
The Living Arabic Project (Classical, Egyptian, Levantine)
Listing of Arabic Dictionaries online by Daniel Varisco.
arabiclexicon.hawramani.com/search by Arabic root in 50+ classical dictionaries plus Lane and Dozy
Philosophical Terms
Arabic and Latin Glossary (philosophy focused, maintained by Dag Nikolaus Hasse, et al.)
Arabic Philosophical Terms (maintained by Andreas Lammer and Raphael Kretz, 2014)
Dictionary of Islamic Philosophical Terms (M. Saeed Sheikh)
Grammars
Wright's Arabic Grammar. Vol. 1 [online]. Vol. 2 [online]. Vols. 1 and 2 [other formats]
Haywood and Nahmad, A New Arabic Grammar of the Written Language (1965). [pdf]
Niʿma, Fuʾād. Mulakhkhaṣ qawāʿid al-lugha al-ʿarabiyya. 19th printing. [pdf]
Ryding, Karin C. A Reference Grammar of Modern Standard Arabic. Cambridge University Press, 2005.
Howell. A Grammar of the Classical Arabic Language (1883). 7 vols. [multiple formats]
Ibn Hishām al-Anṣārī, Sharḥ shudhūr al-dhahab fī maʿrifat kalām al-ʿarab. [online] [other formats]
The Quranic Arabic Corpus: University of Leeds project with full grammatical analysis (iʿrāb) of the Arabic Qur'an and other useful grammatical helps.
Learning Arabic
Cowan, David. An Introduction to Modern Literary Arabic. Cambridge, UK: Cambridge University Press, 1958.
Jones, Alan. Arabic Through the Qur.an. Cambridge, UK: Islamic Texts Society, 2005.
Thackston, W. M. An Introduction to Koranic and Classical Arabic. Bethesda, MD: IBEX Publishers, 1994.
Thackston, W. M. An Introduction to Koranic and Classical Arabic: Key to Exercises. Bethesda, MD: IBEX Publishers, 1994.
Basic Arabic Grammar Vocabulary: One page chart. [pdf]
Roots and Routes Arabic vocabulary learning tool (University of Edinburgh website)
Other Resources
Beeston, A. F. L. Arabic Nomenclature: A Summary Guide for Beginners. [pdf]
English Words of Arabic Ancestry. webpage
Yaqut, Mu'jam al-buldan. [online Vols. 1, 3, 4, and 6] ياقوت، معخم البلدان