'solo-led' is a Modern English compound formed from 'solo' + the past participle 'led' (from 'lead'), literally meaning 'led by a solo (person)'.

'solo' comes into English from Italian/Spanish 'solo', ultimately from Latin 'solus' meaning 'alone'; 'led' is the past participle of 'lead', from Old English 'lǣdan' (to lead). These elements combined in Modern English to form the descriptive compound 'solo-led'.

Initially, 'solo' meant 'alone' (from Latin 'solus') and 'led' meant 'guided' or 'directed' (from Old English 'lǣdan'); over time they combined to produce the compound meaning 'directed or led by one person', used adjectivally.