The word of most frequent use for worship is προσκυνέω, from πρός and κυνέω, ‘to fawn or crouch' and ‘to kiss.' Its first use in scripture is in Gen. 18:2 (LXX), when Abraham prostrates himself on the ground. See also chapter 19:1. Job 31:27 may have reference to an act of worship. It takes in (as ‘worship' once did in English, see 1 Chron. 29:20) all acts of outward honor, such as kneeling, prostration, which were paid to kings and other superiors, as well as to a divine person, or one regarded as such: compare Matt. 18:26; Acts 7:43; 10:25; Rev. 3:9; John 4:22, 23; Rev. 13:12, 15; 16:2; 19:10; &c. So that the word in itself does not determine whether the homage is rendered as to God (which is its most constant use) or not. It might in most passages be translated "do homage."
λατρεύω is another word three times translated 'worship,' of which however the usual rendering is to serve.' Connected as the word is with λάτρον, ‘hire,' its original force is ‘serving for hire,' not of compulsion like a slave. But Biblical Greek has raised the word, with its substantive λατρεία, ‘service,' to higher use, so as never to express any other service but that of God, or of false gods. Thus it most fully answers to the present sense of worship,' and all true service partakes of this character. The Lord meets Satan's proffer of the kingdoms of the world ― "if thou wilt fall down and worship (προσκ.) me” ―with "it is written, Thou shalt worship (προσκ.) the Lord thy God, and him only shalt thou serve (λατρεύω)," thus using both words. Matt. 4:9, 10.
Compare, as to the force of λατρεύω, Luke 1:74; Acts 7:7; 24:14 (worship); Heb. 9:14; 12:28; Rev. 7:15; 22:3: for the worship of idols, Acts 7:42; Rom. 1:25. It is applied also to the services connected with the first covenant, Luke 2:37; Acts 26:7; Rom. 9:4; and Heb. 9:1, 6 (λατρεία), with the omission in the original of divine ' and of God' (as if no longer to be recognized as such), obtruded in each case in the A. V. See also Heb. 8:5; 10:2 (' worshippers '); 13:10. Other passages are Phi. 3:3; Acts 27:23; Rom. 1:9; 2 Tim. 1:3; Rom. 12:1, and, in total contrast, John 16:2 (λατρεία). These are almost all the occurrences.
Worship' is also given as the rendering of two words used in Acts 17 In verse 23 it is for εὐσεβέω, with which may be compared the adjective εὐσεβής ‘devout,' chap. 10:2, 7, and 22:12 and the substantive εὐσέβεια so often found as ‘godliness,' or perhaps better ‘piety' in the Pastoral Epistles and 2 Peter. It embraces not only the reverence well (εὖ) and rightly directed to God, but similarly to parents and others, though the first is the general use of the forms of the word in scripture. It may be rendered in Acts 17:23 "whom therefore ye reverence, not knowing (him)."
θεραπεύω (from θεράπων, ‘an attendant') in Acts 17:25 is ‘to serve,' ‘render service to' (A. V. ‘worship'), constantly used for curing and healing in the gospels; it is nowhere else translated ‘worship.'
One more word, used in this address of Paul in its substantival form, σέβασμα, ‘devotions,' Acts 17:23; and 2 Thess. 2:4, "that is worshipped," leads us to the only passage where the verb occurs, σεβάζομαι, ‘worship,' Rom. 1:25, which is from σέβας, ‘reverence' or ‘awe.' The substantive expresses the object of veneration, altar, image, or shrine, in heathenism, and not ‘devotions,' which has ceased to have this meaning in modern English.